hadoop/hadoop-common-project/hadoop-common/src/main/resources/core-default.xml

<?xml version="1.0"?>
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<configuration>

<!--- global properties -->

<property>
  <name>hadoop.common.configuration.version</name>
  <value>3.0.0</value>
  <description>version of this configuration file</description>
</property>

<property>
  <name>hadoop.tmp.dir</name>
  <value>/tmp/hadoop-${user.name}</value>
  <description>A base for other temporary directories.</description>
</property>

<property>
  <name>hadoop.http.filter.initializers</name>
  <value>org.apache.hadoop.http.lib.StaticUserWebFilter</value>
  <description>A comma separated list of class names. Each class in the list 
  must extend org.apache.hadoop.http.FilterInitializer. The corresponding 
  Filter will be initialized. Then, the Filter will be applied to all user 
  facing jsp and servlet web pages.  The ordering of the list defines the 
  ordering of the filters.</description>
</property>

<!--- security properties -->

<property>
  <name>hadoop.security.authorization</name>
  <value>false</value>
  <description>Is service-level authorization enabled?</description>
</property>

<property>
  <name>hadoop.security.instrumentation.requires.admin</name>
  <value>false</value>
  <description>
    Indicates if administrator ACLs are required to access
    instrumentation servlets (JMX, METRICS, CONF, STACKS).
  </description>
</property>

<property>
  <name>hadoop.security.authentication</name>
  <value>simple</value>
  <description>Possible values are simple (no authentication), and kerberos
  </description>
</property>

<property>
  <name>hadoop.security.group.mapping</name>
  <value>org.apache.hadoop.security.JniBasedUnixGroupsMappingWithFallback</value>
  <description>
    Class for user to group mapping (get groups for a given user) for ACL. 
    The default implementation,
    org.apache.hadoop.security.JniBasedUnixGroupsMappingWithFallback, 
    will determine if the Java Native Interface (JNI) is available. If JNI is 
    available the implementation will use the API within hadoop to resolve a 
    list of groups for a user. If JNI is not available then the shell 
    implementation, ShellBasedUnixGroupsMapping, is used.  This implementation 
    shells out to the Linux/Unix environment with the 
    <code>bash -c groups</code> command to resolve a list of groups for a user.
  </description>
</property>

<property>
  <name>hadoop.security.dns.interface</name>
  <description>
    The name of the Network Interface from which the service should determine
    its host name for Kerberos login. e.g. eth2. In a multi-homed environment,
    the setting can be used to affect the _HOST substitution in the service
    Kerberos principal. If this configuration value is not set, the service
    will use its default hostname as returned by
    InetAddress.getLocalHost().getCanonicalHostName().

    Most clusters will not require this setting.
  </description>
</property>

<property>
  <name>hadoop.security.dns.nameserver</name>
  <description>
    The host name or IP address of the name server (DNS) which a service Node
    should use to determine its own host name for Kerberos Login. Requires
    hadoop.security.dns.interface.

    Most clusters will not require this setting.
  </description>
</property>

<property>
  <name>hadoop.security.dns.log-slow-lookups.enabled</name>
  <value>false</value>
  <description>
    Time name lookups (via SecurityUtil) and log them if they exceed the
    configured threshold.
  </description>
</property>

<property>
  <name>hadoop.security.dns.log-slow-lookups.threshold.ms</name>
  <value>1000</value>
  <description>
    If slow lookup logging is enabled, this threshold is used to decide if a
    lookup is considered slow enough to be logged.
  </description>
</property>

<property>
  <name>hadoop.security.groups.cache.secs</name>
  <value>300</value>
  <description>
    This is the config controlling the validity of the entries in the cache
    containing the user->group mapping. When this duration has expired,
    then the implementation of the group mapping provider is invoked to get
    the groups of the user and then cached back.
  </description>
</property>

<property>
  <name>hadoop.security.groups.negative-cache.secs</name>
  <value>30</value>
  <description>
    Expiration time for entries in the the negative user-to-group mapping
    caching, in seconds. This is useful when invalid users are retrying
    frequently. It is suggested to set a small value for this expiration, since
    a transient error in group lookup could temporarily lock out a legitimate
    user.

    Set this to zero or negative value to disable negative user-to-group caching.
  </description>
</property>

<property>
  <name>hadoop.security.groups.cache.warn.after.ms</name>
  <value>5000</value>
  <description>
    If looking up a single user to group takes longer than this amount of
    milliseconds, we will log a warning message.
  </description>
</property>

<property>
  <name>hadoop.security.groups.cache.background.reload</name>
  <value>false</value>
  <description>
    Whether to reload expired user->group mappings using a background thread
    pool. If set to true, a pool of
    hadoop.security.groups.cache.background.reload.threads is created to
    update the cache in the background.
  </description>
</property>

<property>
  <name>hadoop.security.groups.cache.background.reload.threads</name>
  <value>3</value>
  <description>
    Only relevant if hadoop.security.groups.cache.background.reload is true.
    Controls the number of concurrent background user->group cache entry
    refreshes. Pending refresh requests beyond this value are queued and
    processed when a thread is free.
  </description>
</property>

<property>
  <name>hadoop.security.group.mapping.ldap.connection.timeout.ms</name>
  <value>60000</value>
  <description>
    This property is the connection timeout (in milliseconds) for LDAP
    operations. If the LDAP provider doesn't establish a connection within the
    specified period, it will abort the connect attempt. Non-positive value
    means no LDAP connection timeout is specified in which case it waits for the
    connection to establish until the underlying network times out.
  </description>
</property>

<property>
  <name>hadoop.security.group.mapping.ldap.read.timeout.ms</name>
  <value>60000</value>
  <description>
    This property is the read timeout (in milliseconds) for LDAP
    operations. If the LDAP provider doesn't get a LDAP response within the
    specified period, it will abort the read attempt. Non-positive value
    means no read timeout is specified in which case it waits for the response
    infinitely.
  </description>
</property>

<property>
  <name>hadoop.security.group.mapping.ldap.url</name>
  <value></value>
  <description>
    The URL of the LDAP server to use for resolving user groups when using
    the LdapGroupsMapping user to group mapping.
  </description>
</property>

<property>
  <name>hadoop.security.group.mapping.ldap.ssl</name>
  <value>false</value>
  <description>
    Whether or not to use SSL when connecting to the LDAP server.
  </description>
</property>

<property>
  <name>hadoop.security.group.mapping.ldap.ssl.keystore</name>
  <value></value>
  <description>
    File path to the SSL keystore that contains the SSL certificate required
    by the LDAP server.
  </description>
</property>

<property>
  <name>hadoop.security.group.mapping.ldap.ssl.keystore.password.file</name>
  <value></value>
  <description>
    The path to a file containing the password of the LDAP SSL keystore. If
    the password is not configured in credential providers and the property
    hadoop.security.group.mapping.ldap.ssl.keystore.password is not set,
    LDAPGroupsMapping reads password from the file.

    IMPORTANT: This file should be readable only by the Unix user running
    the daemons and should be a local file.
  </description>
</property>

<property>
  <name>hadoop.security.group.mapping.ldap.ssl.keystore.password</name>
  <value></value>
  <description>
    The password of the LDAP SSL keystore. this property name is used as an
    alias to get the password from credential providers. If the password can
    not be found and hadoop.security.credential.clear-text-fallback is true
    LDAPGroupsMapping uses the value of this property for password.
  </description>
</property>

<property>
  <name>hadoop.security.credential.clear-text-fallback</name>
  <value>true</value>
  <description>
    true or false to indicate whether or not to fall back to storing credential
    password as clear text. The default value is true. This property only works
    when the password can't not be found from credential providers.
  </description>
</property>

<property>
  <name>hadoop.security.credential.provider.path</name>
  <value></value>
  <description>
    A comma-separated list of URLs that indicates the type and
    location of a list of providers that should be consulted.
  </description>
</property>

<property>
  <name>hadoop.security.credstore.java-keystore-provider.password-file</name>
  <value></value>
  <description>
    The path to a file containing the custom password for all keystores
    that may be configured in the provider path.
  </description>
</property>

<property>
  <name>hadoop.security.group.mapping.ldap.bind.user</name>
  <value></value>
  <description>
    The distinguished name of the user to bind as when connecting to the LDAP
    server. This may be left blank if the LDAP server supports anonymous binds.
  </description>
</property>

<property>
  <name>hadoop.security.group.mapping.ldap.bind.password.file</name>
  <value></value>
  <description>
    The path to a file containing the password of the bind user. If
    the password is not configured in credential providers and the property
    hadoop.security.group.mapping.ldap.bind.password is not set,
    LDAPGroupsMapping reads password from the file.

    IMPORTANT: This file should be readable only by the Unix user running
    the daemons and should be a local file.
  </description>
</property>

<property>
  <name>hadoop.security.group.mapping.ldap.bind.password</name>
  <value></value>
  <description>
    The password of the bind user. this property name is used as an
    alias to get the password from credential providers. If the password can
    not be found and hadoop.security.credential.clear-text-fallback is true
    LDAPGroupsMapping uses the value of this property for password.
  </description>
</property>

<property>
  <name>hadoop.security.group.mapping.ldap.base</name>
  <value></value>
  <description>
    The search base for the LDAP connection. This is a distinguished name,
    and will typically be the root of the LDAP directory.
  </description>
</property>

<property>
  <name>hadoop.security.group.mapping.ldap.search.filter.user</name>
  <value>(&amp;(objectClass=user)(sAMAccountName={0}))</value>
  <description>
    An additional filter to use when searching for LDAP users. The default will
    usually be appropriate for Active Directory installations. If connecting to
    an LDAP server with a non-AD schema, this should be replaced with
    (&amp;(objectClass=inetOrgPerson)(uid={0}). {0} is a special string used to
    denote where the username fits into the filter.

    If the LDAP server supports posixGroups, Hadoop can enable the feature by
    setting the value of this property to "posixAccount" and the value of
    the hadoop.security.group.mapping.ldap.search.filter.group property to
    "posixGroup".
  </description>
</property>

<property>
  <name>hadoop.security.group.mapping.ldap.search.filter.group</name>
  <value>(objectClass=group)</value>
  <description>
    An additional filter to use when searching for LDAP groups. This should be
    changed when resolving groups against a non-Active Directory installation.

    See the description of hadoop.security.group.mapping.ldap.search.filter.user
    to enable posixGroups support.
  </description>
</property>

<property>
    <name>hadoop.security.group.mapping.ldap.search.attr.memberof</name>
    <value></value>
    <description>
      The attribute of the user object that identifies its group objects. By
      default, Hadoop makes two LDAP queries per user if this value is empty. If
      set, Hadoop will attempt to resolve group names from this attribute,
      instead of making the second LDAP query to get group objects. The value
      should be 'memberOf' for an MS AD installation.
    </description>
</property>

<property>
  <name>hadoop.security.group.mapping.ldap.search.attr.member</name>
  <value>member</value>
  <description>
    The attribute of the group object that identifies the users that are
    members of the group. The default will usually be appropriate for
    any LDAP installation.
  </description>
</property>

<property>
  <name>hadoop.security.group.mapping.ldap.search.attr.group.name</name>
  <value>cn</value>
  <description>
    The attribute of the group object that identifies the group name. The
    default will usually be appropriate for all LDAP systems.
  </description>
</property>

<property>
  <name>hadoop.security.group.mapping.ldap.search.group.hierarchy.levels</name>
  <value>0</value>
  <description>
    The number of levels to go up the group hierarchy when determining
    which groups a user is part of. 0 Will represent checking just the
    group that the user belongs to.  Each additional level will raise the
    time it takes to execute a query by at most
    hadoop.security.group.mapping.ldap.directory.search.timeout.
    The default will usually be appropriate for all LDAP systems.
  </description>
</property>

<property>
  <name>hadoop.security.group.mapping.ldap.posix.attr.uid.name</name>
  <value>uidNumber</value>
  <description>
    The attribute of posixAccount to use when groups for membership.
    Mostly useful for schemas wherein groups have memberUids that use an
    attribute other than uidNumber.
  </description>
</property>

<property>
  <name>hadoop.security.group.mapping.ldap.posix.attr.gid.name</name>
  <value>gidNumber</value>
  <description>
    The attribute of posixAccount indicating the group id.
  </description>
</property>

<property>
  <name>hadoop.security.group.mapping.ldap.directory.search.timeout</name>
  <value>10000</value>
  <description>
    The attribute applied to the LDAP SearchControl properties to set a
    maximum time limit when searching and awaiting a result.
    Set to 0 if infinite wait period is desired.
    Default is 10 seconds. Units in milliseconds.
  </description>
</property>

<property>
  <name>hadoop.security.group.mapping.providers</name>
  <value></value>
  <description>
    Comma separated of names of other providers to provide user to group
    mapping. Used by CompositeGroupsMapping.
  </description>
</property>

<property>
  <name>hadoop.security.group.mapping.providers.combined</name>
  <value>true</value>
  <description>
    true or false to indicate whether groups from the providers are combined or
    not. The default value is true. If true, then all the providers will be
    tried to get groups and all the groups are combined to return as the final
    results. Otherwise, providers are tried one by one in the configured list
    order, and if any groups are retrieved from any provider, then the groups
    will be returned without trying the left ones.
  </description>
</property>

<property>
  <name>hadoop.security.service.user.name.key</name>
  <value></value>
  <description>
    For those cases where the same RPC protocol is implemented by multiple
    servers, this configuration is required for specifying the principal
    name to use for the service when the client wishes to make an RPC call.
  </description>
</property>


<property>
    <name>hadoop.security.uid.cache.secs</name>
    <value>14400</value>
    <description>
        This is the config controlling the validity of the entries in the cache
        containing the userId to userName and groupId to groupName used by
        NativeIO getFstat().
    </description>
</property>

<property>
  <name>hadoop.rpc.protection</name>
  <value>authentication</value>
  <description>A comma-separated list of protection values for secured sasl 
      connections. Possible values are authentication, integrity and privacy.
      authentication means authentication only and no integrity or privacy; 
      integrity implies authentication and integrity are enabled; and privacy 
      implies all of authentication, integrity and privacy are enabled.
      hadoop.security.saslproperties.resolver.class can be used to override
      the hadoop.rpc.protection for a connection at the server side.
  </description>
</property>

<property>
  <name>hadoop.security.saslproperties.resolver.class</name>
  <value></value>
  <description>SaslPropertiesResolver used to resolve the QOP used for a 
      connection. If not specified, the full set of values specified in 
      hadoop.rpc.protection is used while determining the QOP used for the 
      connection. If a class is specified, then the QOP values returned by 
      the class will be used while determining the QOP used for the connection.
  </description>
</property>

<property>
  <name>hadoop.security.sensitive-config-keys</name>
  <value>password$,fs.s3.*[Ss]ecret.?[Kk]ey,fs.azure.account.key.*,dfs.webhdfs.oauth2.[a-z]+.token,hadoop.security.sensitive-config-keys</value>
  <description>A comma-separated list of regular expressions to match against
      configuration keys that should be redacted where appropriate, for
      example, when logging modified properties during a reconfiguration,
      private credentials should not be logged.
  </description>
</property>

<property>
  <name>hadoop.workaround.non.threadsafe.getpwuid</name>
  <value>true</value>
  <description>Some operating systems or authentication modules are known to
  have broken implementations of getpwuid_r and getpwgid_r, such that these
  calls are not thread-safe. Symptoms of this problem include JVM crashes
  with a stack trace inside these functions. If your system exhibits this
  issue, enable this configuration parameter to include a lock around the
  calls as a workaround.

  An incomplete list of some systems known to have this issue is available
  at http://wiki.apache.org/hadoop/KnownBrokenPwuidImplementations
  </description>
</property>

<property>
  <name>hadoop.kerberos.kinit.command</name>
  <value>kinit</value>
  <description>Used to periodically renew Kerberos credentials when provided
  to Hadoop. The default setting assumes that kinit is in the PATH of users
  running the Hadoop client. Change this to the absolute path to kinit if this
  is not the case.
  </description>
</property>

<property>
    <name>hadoop.kerberos.min.seconds.before.relogin</name>
    <value>60</value>
    <description>The minimum time between relogin attempts for Kerberos, in
    seconds.
    </description>
</property>

<property>
  <name>hadoop.security.auth_to_local</name>
  <value></value>
  <description>Maps kerberos principals to local user names</description>
</property>

<property>
  <name>hadoop.token.files</name>
  <value></value>
  <description>List of token cache files that have delegation tokens for hadoop service</description>
</property>

<!-- i/o properties -->
<property>
  <name>io.file.buffer.size</name>
  <value>4096</value>
  <description>The size of buffer for use in sequence files.
  The size of this buffer should probably be a multiple of hardware
  page size (4096 on Intel x86), and it determines how much data is
  buffered during read and write operations.</description>
</property>
  
<property>
  <name>io.bytes.per.checksum</name>
  <value>512</value>
  <description>The number of bytes per checksum.  Must not be larger than
  io.file.buffer.size.</description>
</property>

<property>
  <name>io.skip.checksum.errors</name>
  <value>false</value>
  <description>If true, when a checksum error is encountered while
  reading a sequence file, entries are skipped, instead of throwing an
  exception.</description>
</property>

<property>
  <name>io.compression.codecs</name>
  <value></value>
  <description>A comma-separated list of the compression codec classes that can
  be used for compression/decompression. In addition to any classes specified
  with this property (which take precedence), codec classes on the classpath
  are discovered using a Java ServiceLoader.</description>
</property>

<property>
  <name>io.compression.codec.bzip2.library</name>
  <value>system-native</value>
  <description>The native-code library to be used for compression and
  decompression by the bzip2 codec.  This library could be specified
  either by by name or the full pathname.  In the former case, the
  library is located by the dynamic linker, usually searching the
  directories specified in the environment variable LD_LIBRARY_PATH.
  
  The value of "system-native" indicates that the default system
  library should be used.  To indicate that the algorithm should
  operate entirely in Java, specify "java-builtin".</description>
</property>

<property>
  <name>io.serializations</name>
  <value>org.apache.hadoop.io.serializer.WritableSerialization, org.apache.hadoop.io.serializer.avro.AvroSpecificSerialization, org.apache.hadoop.io.serializer.avro.AvroReflectSerialization</value>
  <description>A list of serialization classes that can be used for
  obtaining serializers and deserializers.</description>
</property>

<property>
  <name>io.seqfile.local.dir</name>
  <value>${hadoop.tmp.dir}/io/local</value>
  <description>The local directory where sequence file stores intermediate
  data files during merge.  May be a comma-separated list of
  directories on different devices in order to spread disk i/o.
  Directories that do not exist are ignored.
  </description>
</property>

<property>
  <name>io.map.index.skip</name>
  <value>0</value>
  <description>Number of index entries to skip between each entry.
  Zero by default. Setting this to values larger than zero can
  facilitate opening large MapFiles using less memory.</description>
</property>

<property>
  <name>io.map.index.interval</name>
  <value>128</value>
  <description>
    MapFile consist of two files - data file (tuples) and index file
    (keys). For every io.map.index.interval records written in the
    data file, an entry (record-key, data-file-position) is written
    in the index file. This is to allow for doing binary search later
    within the index file to look up records by their keys and get their
    closest positions in the data file.
  </description>
</property>

<property>
  <name>io.erasurecode.codec.rs-default.rawcoder</name>
  <value>org.apache.hadoop.io.erasurecode.rawcoder.RSRawErasureCoderFactory</value>
  <description>
    Raw coder implementation for the rs-default codec.
  </description>
</property>

<!-- file system properties -->

<property>
  <name>fs.defaultFS</name>
  <value>file:///</value>
  <description>The name of the default file system.  A URI whose
  scheme and authority determine the FileSystem implementation.  The
  uri's scheme determines the config property (fs.SCHEME.impl) naming
  the FileSystem implementation class.  The uri's authority is used to
  determine the host, port, etc. for a filesystem.</description>
</property>

<property>
  <name>fs.default.name</name>
  <value>file:///</value>
  <description>Deprecated. Use (fs.defaultFS) property
  instead</description>
</property>

<property>
  <name>fs.trash.interval</name>
  <value>0</value>
  <description>Number of minutes after which the checkpoint
  gets deleted.  If zero, the trash feature is disabled.
  This option may be configured both on the server and the
  client. If trash is disabled server side then the client
  side configuration is checked. If trash is enabled on the
  server side then the value configured on the server is
  used and the client configuration value is ignored.
  </description>
</property>

<property>
  <name>fs.trash.checkpoint.interval</name>
  <value>0</value>
  <description>Number of minutes between trash checkpoints.
  Should be smaller or equal to fs.trash.interval. If zero,
  the value is set to the value of fs.trash.interval.
  Every time the checkpointer runs it creates a new checkpoint 
  out of current and removes checkpoints created more than 
  fs.trash.interval minutes ago.
  </description>
</property>

<property>
  <name>fs.protected.directories</name>
  <value></value>
  <description>A comma-separated list of directories which cannot
    be deleted even by the superuser unless they are empty. This
    setting can be used to guard important system directories
    against accidental deletion due to administrator error.
  </description>
</property>

<property>
  <name>fs.AbstractFileSystem.file.impl</name>
  <value>org.apache.hadoop.fs.local.LocalFs</value>
  <description>The AbstractFileSystem for file: uris.</description>
</property>

<property>
  <name>fs.AbstractFileSystem.har.impl</name>
  <value>org.apache.hadoop.fs.HarFs</value>
  <description>The AbstractFileSystem for har: uris.</description>
</property> 

<property>
  <name>fs.AbstractFileSystem.hdfs.impl</name>
  <value>org.apache.hadoop.fs.Hdfs</value>
  <description>The FileSystem for hdfs: uris.</description>
</property>

<property>
  <name>fs.AbstractFileSystem.viewfs.impl</name>
  <value>org.apache.hadoop.fs.viewfs.ViewFs</value>
  <description>The AbstractFileSystem for view file system for viewfs: uris
  (ie client side mount table:).</description>
</property>

<property>
  <name>fs.AbstractFileSystem.ftp.impl</name>
  <value>org.apache.hadoop.fs.ftp.FtpFs</value>
  <description>The FileSystem for Ftp: uris.</description>
</property>

<property>
  <name>fs.AbstractFileSystem.webhdfs.impl</name>
  <value>org.apache.hadoop.fs.WebHdfs</value>
  <description>The FileSystem for webhdfs: uris.</description>
</property>

<property>
  <name>fs.AbstractFileSystem.swebhdfs.impl</name>
  <value>org.apache.hadoop.fs.SWebHdfs</value>
  <description>The FileSystem for swebhdfs: uris.</description>
</property>

<property>
  <name>fs.ftp.host</name>
  <value>0.0.0.0</value>
  <description>FTP filesystem connects to this server</description>
</property>

<property>
  <name>fs.ftp.host.port</name>
  <value>21</value>
  <description>
    FTP filesystem connects to fs.ftp.host on this port
  </description>
</property>

<property>
  <name>fs.df.interval</name>
  <value>60000</value>
  <description>Disk usage statistics refresh interval in msec.</description>
</property>

<property>
  <name>fs.du.interval</name>
  <value>600000</value>
  <description>File space usage statistics refresh interval in msec.</description>
</property>

<property>
  <name>fs.s3n.buffer.dir</name>
  <value>${hadoop.tmp.dir}/s3n</value>
  <description>Determines where on the local filesystem the s3n:// filesystem
  should store files before sending them to S3
  (or after retrieving them from S3).
  </description>
</property>

<property>
  <name>fs.s3n.maxRetries</name>
  <value>4</value>
  <description>The maximum number of retries for reading or writing files to S3, 
  before we signal failure to the application.
  </description>
</property>

<property>
  <name>fs.s3n.sleepTimeSeconds</name>
  <value>10</value>
  <description>The number of seconds to sleep between each S3 retry.
  </description>
</property>

<property>
  <name>fs.automatic.close</name>
  <value>true</value>
  <description>By default, FileSystem instances are automatically closed at program
  exit using a JVM shutdown hook. Setting this property to false disables this
  behavior. This is an advanced option that should only be used by server applications
  requiring a more carefully orchestrated shutdown sequence.
  </description>
</property>

<property>
  <name>fs.s3n.awsAccessKeyId</name>
  <description>AWS access key ID used by S3 native file system.</description>
</property>

<property>
  <name>fs.s3n.awsSecretAccessKey</name>
  <description>AWS secret key used by S3 native file system.</description>
</property>

<property>
  <name>fs.s3n.block.size</name>
  <value>67108864</value>
  <description>Block size to use when reading files using the native S3
  filesystem (s3n: URIs).</description>
</property>

<property>
  <name>fs.s3n.multipart.uploads.enabled</name>
  <value>false</value>
  <description>Setting this property to true enables multiple uploads to
  native S3 filesystem. When uploading a file, it is split into blocks
  if the size is larger than fs.s3n.multipart.uploads.block.size.
  </description>
</property>

<property>
  <name>fs.s3n.multipart.uploads.block.size</name>
  <value>67108864</value>
  <description>The block size for multipart uploads to native S3 filesystem.
  Default size is 64MB.
  </description>
</property>

<property>
  <name>fs.s3n.multipart.copy.block.size</name>
  <value>5368709120</value>
  <description>The block size for multipart copy in native S3 filesystem.
  Default size is 5GB.
  </description>
</property>

<property>
  <name>fs.s3n.server-side-encryption-algorithm</name>
  <value></value>
  <description>Specify a server-side encryption algorithm for S3.
  Unset by default, and the only other currently allowable value is AES256.
  </description>
</property>

<property>
  <name>fs.s3a.access.key</name>
  <description>AWS access key ID used by S3A file system. Omit for IAM role-based or provider-based authentication.</description>
</property>

<property>
  <name>fs.s3a.secret.key</name>
  <description>AWS secret key used by S3A file system. Omit for IAM role-based or provider-based authentication.</description>
</property>

<property>
  <name>fs.s3a.aws.credentials.provider</name>
  <description>
    Comma-separated class names of credential provider classes which implement
    com.amazonaws.auth.AWSCredentialsProvider.

    These are loaded and queried in sequence for a valid set of credentials.
    Each listed class must provide either an accessible constructor accepting
    java.net.URI and org.apache.hadoop.conf.Configuration, or an accessible
    default constructor.

    Specifying org.apache.hadoop.fs.s3a.AnonymousAWSCredentialsProvider allows
    anonymous access to a publicly accessible S3 bucket without any credentials.
    Please note that allowing anonymous access to an S3 bucket compromises
    security and therefore is unsuitable for most use cases. It can be useful
    for accessing public data sets without requiring AWS credentials.
  </description>
</property>

<property>
  <name>fs.s3a.session.token</name>
  <description>Session token, when using org.apache.hadoop.fs.s3a.TemporaryAWSCredentialsProvider
    as one of the providers.
  </description>
</property>

<property>
  <name>fs.s3a.connection.maximum</name>
  <value>15</value>
  <description>Controls the maximum number of simultaneous connections to S3.</description>
</property>

<property>
  <name>fs.s3a.connection.ssl.enabled</name>
  <value>true</value>
  <description>Enables or disables SSL connections to S3.</description>
</property>

<property>
  <name>fs.s3a.endpoint</name>
  <description>AWS S3 endpoint to connect to. An up-to-date list is
    provided in the AWS Documentation: regions and endpoints. Without this
    property, the standard region (s3.amazonaws.com) is assumed.
  </description>
</property>

<property>
  <name>fs.s3a.path.style.access</name>
  <value>false</value>
  <description>Enable S3 path style access ie disabling the default virtual hosting behaviour.
    Useful for S3A-compliant storage providers as it removes the need to set up DNS for virtual hosting.
  </description>
</property>

<property>
  <name>fs.s3a.proxy.host</name>
  <description>Hostname of the (optional) proxy server for S3 connections.</description>
</property>

<property>
  <name>fs.s3a.proxy.port</name>
  <description>Proxy server port. If this property is not set
    but fs.s3a.proxy.host is, port 80 or 443 is assumed (consistent with
    the value of fs.s3a.connection.ssl.enabled).</description>
</property>

<property>
  <name>fs.s3a.proxy.username</name>
  <description>Username for authenticating with proxy server.</description>
</property>

<property>
  <name>fs.s3a.proxy.password</name>
  <description>Password for authenticating with proxy server.</description>
</property>

<property>
  <name>fs.s3a.proxy.domain</name>
  <description>Domain for authenticating with proxy server.</description>
</property>

<property>
  <name>fs.s3a.proxy.workstation</name>
  <description>Workstation for authenticating with proxy server.</description>
</property>

<property>
  <name>fs.s3a.attempts.maximum</name>
  <value>20</value>
  <description>How many times we should retry commands on transient errors.</description>
</property>

<property>
  <name>fs.s3a.connection.establish.timeout</name>
  <value>5000</value>
  <description>Socket connection setup timeout in milliseconds.</description>
</property>

<property>
  <name>fs.s3a.connection.timeout</name>
  <value>200000</value>
  <description>Socket connection timeout in milliseconds.</description>
</property>

<property>
  <name>fs.s3a.socket.send.buffer</name>
  <value>8192</value>
  <description>Socket send buffer hint to amazon connector. Represented in bytes.</description>
</property>

<property>
  <name>fs.s3a.socket.recv.buffer</name>
  <value>8192</value>
  <description>Socket receive buffer hint to amazon connector. Represented in bytes.</description>
</property>

<property>
  <name>fs.s3a.paging.maximum</name>
  <value>5000</value>
  <description>How many keys to request from S3 when doing 
     directory listings at a time.</description>
</property>

<property>
  <name>fs.s3a.threads.max</name>
  <value>10</value>
  <description>The total number of threads available in the filesystem for data
    uploads *or any other queued filesystem operation*.</description>
</property>

<property>
  <name>fs.s3a.threads.keepalivetime</name>
  <value>60</value>
  <description>Number of seconds a thread can be idle before being
    terminated.</description>
</property>

<property>
  <name>fs.s3a.max.total.tasks</name>
  <value>5</value>
  <description>The number of operations which can be queued for execution</description>
</property>

<property>
  <name>fs.s3a.multipart.size</name>
  <value>104857600</value>
  <description>How big (in bytes) to split upload or copy operations up into.</description>
</property>

<property>
  <name>fs.s3a.multipart.threshold</name>
  <value>2147483647</value>
  <description>How big (in bytes) to split upload or copy operations up into.
    This also controls the partition size in renamed files, as rename() involves
    copying the source file(s)
  </description>
</property>

<property>
  <name>fs.s3a.multiobjectdelete.enable</name>
  <value>true</value>
  <description>When enabled, multiple single-object delete requests are replaced by
    a single 'delete multiple objects'-request, reducing the number of requests.
    Beware: legacy S3-compatible object stores might not support this request.
  </description>
</property>

<property>
  <name>fs.s3a.acl.default</name>
  <description>Set a canned ACL for newly created and copied objects. Value may be Private,
      PublicRead, PublicReadWrite, AuthenticatedRead, LogDeliveryWrite, BucketOwnerRead,
      or BucketOwnerFullControl.</description>
</property>

<property>
  <name>fs.s3a.multipart.purge</name>
  <value>false</value>
  <description>True if you want to purge existing multipart uploads that may not have been
    completed/aborted correctly. The corresponding purge age is defined in
    fs.s3a.multipart.purge.age.
    If set, when the filesystem is instantiated then all outstanding uploads
    older than the purge age will be terminated -across the entire bucket.
    This will impact multipart uploads by other applications and users. so should
    be used sparingly, with an age value chosen to stop failed uploads, without
    breaking ongoing operations.
  </description>
</property>

<property>
  <name>fs.s3a.multipart.purge.age</name>
  <value>86400</value>
  <description>Minimum age in seconds of multipart uploads to purge.
  </description>
</property>

<property>
  <name>fs.s3a.server-side-encryption-algorithm</name>
  <description>Specify a server-side encryption algorithm for s3a: file system.
    Unset by default, and the only other currently allowable value is AES256.
  </description>
</property>

<property>
  <name>fs.s3a.signing-algorithm</name>
  <description>Override the default signing algorithm so legacy
    implementations can still be used</description>
</property>

<property>
  <name>fs.s3a.block.size</name>
  <value>33554432</value>
  <description>Block size to use when reading files using s3a: file system.
  </description>
</property>

<property>
  <name>fs.s3a.buffer.dir</name>
  <value>${hadoop.tmp.dir}/s3a</value>
  <description>Comma separated list of directories that will be used to buffer file 
    uploads to.</description>
</property>

<property>
  <name>fs.s3a.fast.upload</name>
  <value>false</value>
  <description>
    Use the incremental block-based fast upload mechanism with
    the buffering mechanism set in fs.s3a.fast.upload.buffer.
  </description>
</property>

<property>
  <name>fs.s3a.fast.upload.buffer</name>
  <value>disk</value>
  <description>
    The buffering mechanism to use when using S3A fast upload
    (fs.s3a.fast.upload=true). Values: disk, array, bytebuffer.
    This configuration option has no effect if fs.s3a.fast.upload is false.

    "disk" will use the directories listed in fs.s3a.buffer.dir as
    the location(s) to save data prior to being uploaded.

    "array" uses arrays in the JVM heap

    "bytebuffer" uses off-heap memory within the JVM.

    Both "array" and "bytebuffer" will consume memory in a single stream up to the number
    of blocks set by:

        fs.s3a.multipart.size * fs.s3a.fast.upload.active.blocks.

    If using either of these mechanisms, keep this value low

    The total number of threads performing work across all threads is set by
    fs.s3a.threads.max, with fs.s3a.max.total.tasks values setting the number of queued
    work items.
  </description>
</property>

<property>
  <name>fs.s3a.fast.upload.active.blocks</name>
  <value>4</value>
  <description>
    Maximum Number of blocks a single output stream can have
    active (uploading, or queued to the central FileSystem
    instance's pool of queued operations.

    This stops a single stream overloading the shared thread pool.
  </description>
</property>

<property>
  <name>fs.s3a.readahead.range</name>
  <value>65536</value>
  <description>Bytes to read ahead during a seek() before closing and
  re-opening the S3 HTTP connection. This option will be overridden if
  any call to setReadahead() is made to an open stream.</description>
</property>

<property>
  <name>fs.s3a.user.agent.prefix</name>
  <value></value>
  <description>
    Sets a custom value that will be prepended to the User-Agent header sent in
    HTTP requests to the S3 back-end by S3AFileSystem.  The User-Agent header
    always includes the Hadoop version number followed by a string generated by
    the AWS SDK.  An example is "User-Agent: Hadoop 2.8.0, aws-sdk-java/1.10.6".
    If this optional property is set, then its value is prepended to create a
    customized User-Agent.  For example, if this configuration property was set
    to "MyApp", then an example of the resulting User-Agent would be
    "User-Agent: MyApp, Hadoop 2.8.0, aws-sdk-java/1.10.6".
  </description>
</property>

<property>
  <name>fs.s3a.impl</name>
  <value>org.apache.hadoop.fs.s3a.S3AFileSystem</value>
  <description>The implementation class of the S3A Filesystem</description>
</property>

<property>
  <name>fs.AbstractFileSystem.s3a.impl</name>
  <value>org.apache.hadoop.fs.s3a.S3A</value>
  <description>The implementation class of the S3A AbstractFileSystem.</description>
</property>

<property>
  <name>io.seqfile.compress.blocksize</name>
  <value>1000000</value>
  <description>The minimum block size for compression in block compressed 
          SequenceFiles.
  </description>
</property>

<property>
  <name>io.seqfile.lazydecompress</name>
  <value>true</value>
  <description>Should values of block-compressed SequenceFiles be decompressed
          only when necessary.
  </description>
</property>

<property>
  <name>io.seqfile.sorter.recordlimit</name>
  <value>1000000</value>
  <description>The limit on number of records to be kept in memory in a spill 
          in SequenceFiles.Sorter
  </description>
</property>

 <property>
  <name>io.mapfile.bloom.size</name>
  <value>1048576</value>
  <description>The size of BloomFilter-s used in BloomMapFile. Each time this many
  keys is appended the next BloomFilter will be created (inside a DynamicBloomFilter).
  Larger values minimize the number of filters, which slightly increases the performance,
  but may waste too much space if the total number of keys is usually much smaller
  than this number.
  </description>
</property>

<property>
  <name>io.mapfile.bloom.error.rate</name>
  <value>0.005</value>
  <description>The rate of false positives in BloomFilter-s used in BloomMapFile.
  As this value decreases, the size of BloomFilter-s increases exponentially. This
  value is the probability of encountering false positives (default is 0.5%).
  </description>
</property>

<property>
  <name>hadoop.util.hash.type</name>
  <value>murmur</value>
  <description>The default implementation of Hash. Currently this can take one of the
  two values: 'murmur' to select MurmurHash and 'jenkins' to select JenkinsHash.
  </description>
</property>


<!-- ipc properties -->

<property>
  <name>ipc.client.idlethreshold</name>
  <value>4000</value>
  <description>Defines the threshold number of connections after which
               connections will be inspected for idleness.
  </description>
</property>

<property>
  <name>ipc.client.kill.max</name>
  <value>10</value>
  <description>Defines the maximum number of clients to disconnect in one go.
  </description>
</property>

<property>
  <name>ipc.client.connection.maxidletime</name>
  <value>10000</value>
  <description>The maximum time in msec after which a client will bring down the
               connection to the server.
  </description>
</property>

<property>
  <name>ipc.client.connect.max.retries</name>
  <value>10</value>
  <description>Indicates the number of retries a client will make to establish
               a server connection.
  </description>
</property>

<property>
  <name>ipc.client.connect.retry.interval</name>
  <value>1000</value>
  <description>Indicates the number of milliseconds a client will wait for
    before retrying to establish a server connection.
  </description>
</property>

<property>
  <name>ipc.client.connect.timeout</name>
  <value>20000</value>
  <description>Indicates the number of milliseconds a client will wait for the 
               socket to establish a server connection.
  </description>
</property>

<property>
  <name>ipc.client.connect.max.retries.on.timeouts</name>
  <value>45</value>
  <description>Indicates the number of retries a client will make on socket timeout
               to establish a server connection.
  </description>
</property>

<property>
  <name>ipc.client.tcpnodelay</name>
  <value>true</value>
  <description>Use TCP_NODELAY flag to bypass Nagle's algorithm transmission delays.
  </description>
</property>

<property>
  <name>ipc.client.low-latency</name>
  <value>false</value>
  <description>Use low-latency QoS markers for IPC connections.
  </description>
</property>

<property>
  <name>ipc.client.ping</name>
  <value>true</value>
  <description>Send a ping to the server when timeout on reading the response,
  if set to true. If no failure is detected, the client retries until at least
  a byte is read or the time given by ipc.client.rpc-timeout.ms is passed.
  </description>
</property>

<property>
  <name>ipc.ping.interval</name>
  <value>60000</value>
  <description>Timeout on waiting response from server, in milliseconds.
  The client will send ping when the interval is passed without receiving bytes,
  if ipc.client.ping is set to true.
  </description>
</property>

<property>
  <name>ipc.client.rpc-timeout.ms</name>
  <value>0</value>
  <description>Timeout on waiting response from server, in milliseconds.
  If ipc.client.ping is set to true and this rpc-timeout is greater than
  the value of ipc.ping.interval, the effective value of the rpc-timeout is
  rounded up to multiple of ipc.ping.interval.
  </description>
</property>

<property>
  <name>ipc.server.listen.queue.size</name>
  <value>128</value>
  <description>Indicates the length of the listen queue for servers accepting
               client connections.
  </description>
</property>

<property>
    <name>ipc.server.log.slow.rpc</name>
    <value>false</value>
    <description>This setting is useful to troubleshoot performance issues for
     various services. If this value is set to true then we log requests that
     fall into 99th percentile as well as increment RpcSlowCalls counter.
    </description>
</property>

<property>
  <name>ipc.maximum.data.length</name>
  <value>67108864</value>
  <description>This indicates the maximum IPC message length (bytes) that can be
    accepted by the server. Messages larger than this value are rejected by the
    immediately to avoid possible OOMs. This setting should rarely need to be
    changed.
  </description>
</property>

<property>
  <name>ipc.maximum.response.length</name>
  <value>134217728</value>
  <description>This indicates the maximum IPC message length (bytes) that can be
    accepted by the client. Messages larger than this value are rejected
    immediately to avoid possible OOMs. This setting should rarely need to be
    changed.  Set to 0 to disable.
  </description>
</property>

<!-- Proxy Configuration -->

<property>
  <name>hadoop.security.impersonation.provider.class</name>
  <value></value>
  <description>A class which implements ImpersonationProvider interface, used to 
       authorize whether one user can impersonate a specific user. 
       If not specified, the DefaultImpersonationProvider will be used. 
       If a class is specified, then that class will be used to determine 
       the impersonation capability.
  </description>
</property>

<property>
  <name>hadoop.rpc.socket.factory.class.default</name>
  <value>org.apache.hadoop.net.StandardSocketFactory</value>
  <description> Default SocketFactory to use. This parameter is expected to be
    formatted as "package.FactoryClassName".
  </description>
</property>

<property>
  <name>hadoop.rpc.socket.factory.class.ClientProtocol</name>
  <value></value>
  <description> SocketFactory to use to connect to a DFS. If null or empty, use
    hadoop.rpc.socket.class.default. This socket factory is also used by
    DFSClient to create sockets to DataNodes.
  </description>
</property>



<property>
  <name>hadoop.socks.server</name>
  <value></value>
  <description> Address (host:port) of the SOCKS server to be used by the
    SocksSocketFactory.
  </description>
</property>

<!-- Topology Configuration -->
<property>
  <name>net.topology.node.switch.mapping.impl</name>
  <value>org.apache.hadoop.net.ScriptBasedMapping</value>
  <description> The default implementation of the DNSToSwitchMapping. It
    invokes a script specified in net.topology.script.file.name to resolve
    node names. If the value for net.topology.script.file.name is not set, the
    default value of DEFAULT_RACK is returned for all node names.
  </description>
</property>

<property>
  <name>net.topology.impl</name>
  <value>org.apache.hadoop.net.NetworkTopology</value>
  <description> The default implementation of NetworkTopology which is classic three layer one.
  </description>
</property>

<property>
  <name>net.topology.script.file.name</name>
  <value></value>
  <description> The script name that should be invoked to resolve DNS names to
    NetworkTopology names. Example: the script would take host.foo.bar as an
    argument, and return /rack1 as the output.
  </description>
</property>

<property>
  <name>net.topology.script.number.args</name>
  <value>100</value>
  <description> The max number of args that the script configured with 
    net.topology.script.file.name should be run with. Each arg is an
    IP address.
  </description>
</property>

<property>
  <name>net.topology.table.file.name</name>
  <value></value>
  <description> The file name for a topology file, which is used when the
    net.topology.node.switch.mapping.impl property is set to
    org.apache.hadoop.net.TableMapping. The file format is a two column text
    file, with columns separated by whitespace. The first column is a DNS or
    IP address and the second column specifies the rack where the address maps.
    If no entry corresponding to a host in the cluster is found, then 
    /default-rack is assumed.
  </description>
</property>

<!-- Local file system -->
<property>
  <name>file.stream-buffer-size</name>
  <value>4096</value>
  <description>The size of buffer to stream files.
  The size of this buffer should probably be a multiple of hardware
  page size (4096 on Intel x86), and it determines how much data is
  buffered during read and write operations.</description>
</property>

<property>
  <name>file.bytes-per-checksum</name>
  <value>512</value>
  <description>The number of bytes per checksum.  Must not be larger than
  file.stream-buffer-size</description>
</property>

<property>
  <name>file.client-write-packet-size</name>
  <value>65536</value>
  <description>Packet size for clients to write</description>
</property>

<property>
  <name>file.blocksize</name>
  <value>67108864</value>
  <description>Block size</description>
</property>

<property>
  <name>file.replication</name>
  <value>1</value>
  <description>Replication factor</description>
</property>

<!-- s3native File System -->

<property>
  <name>s3native.stream-buffer-size</name>
  <value>4096</value>
  <description>The size of buffer to stream files.
  The size of this buffer should probably be a multiple of hardware
  page size (4096 on Intel x86), and it determines how much data is
  buffered during read and write operations.</description>
</property>

<property>
  <name>s3native.bytes-per-checksum</name>
  <value>512</value>
  <description>The number of bytes per checksum.  Must not be larger than
  s3native.stream-buffer-size</description>
</property>

<property>
  <name>s3native.client-write-packet-size</name>
  <value>65536</value>
  <description>Packet size for clients to write</description>
</property>

<property>
  <name>s3native.blocksize</name>
  <value>67108864</value>
  <description>Block size</description>
</property>

<property>
  <name>s3native.replication</name>
  <value>3</value>
  <description>Replication factor</description>
</property>

<!-- FTP file system -->
<property>
  <name>ftp.stream-buffer-size</name>
  <value>4096</value>
  <description>The size of buffer to stream files.
  The size of this buffer should probably be a multiple of hardware
  page size (4096 on Intel x86), and it determines how much data is
  buffered during read and write operations.</description>
</property>

<property>
  <name>ftp.bytes-per-checksum</name>
  <value>512</value>
  <description>The number of bytes per checksum.  Must not be larger than
  ftp.stream-buffer-size</description>
</property>

<property>
  <name>ftp.client-write-packet-size</name>
  <value>65536</value>
  <description>Packet size for clients to write</description>
</property>

<property>
  <name>ftp.blocksize</name>
  <value>67108864</value>
  <description>Block size</description>
</property>

<property>
  <name>ftp.replication</name>
  <value>3</value>
  <description>Replication factor</description>
</property>

<!-- Tfile -->

<property>
  <name>tfile.io.chunk.size</name>
  <value>1048576</value>
  <description>
    Value chunk size in bytes. Default  to
    1MB. Values of the length less than the chunk size is
    guaranteed to have known value length in read time (See also
    TFile.Reader.Scanner.Entry.isValueLengthKnown()).
  </description>
</property>

<property>
  <name>tfile.fs.output.buffer.size</name>
  <value>262144</value>
  <description>
    Buffer size used for FSDataOutputStream in bytes.
  </description>
</property>

<property>
  <name>tfile.fs.input.buffer.size</name>
  <value>262144</value>
  <description>
    Buffer size used for FSDataInputStream in bytes.
  </description>
</property>

<!-- HTTP web-consoles Authentication -->

<property>
  <name>hadoop.http.authentication.type</name>
  <value>simple</value>
  <description>
    Defines authentication used for Oozie HTTP endpoint.
    Supported values are: simple | kerberos | #AUTHENTICATION_HANDLER_CLASSNAME#
  </description>
</property>

<property>
  <name>hadoop.http.authentication.token.validity</name>
  <value>36000</value>
  <description>
    Indicates how long (in seconds) an authentication token is valid before it has
    to be renewed.
  </description>
</property>

<property>
  <name>hadoop.http.authentication.signature.secret.file</name>
  <value>${user.home}/hadoop-http-auth-signature-secret</value>
  <description>
    The signature secret for signing the authentication tokens.
    The same secret should be used for JT/NN/DN/TT configurations.
  </description>
</property>

<property>
  <name>hadoop.http.authentication.cookie.domain</name>
  <value></value>
  <description>
    The domain to use for the HTTP cookie that stores the authentication token.
    In order to authentiation to work correctly across all Hadoop nodes web-consoles
    the domain must be correctly set.
    IMPORTANT: when using IP addresses, browsers ignore cookies with domain settings.
    For this setting to work properly all nodes in the cluster must be configured
    to generate URLs with hostname.domain names on it.
  </description>
</property>

<property>
  <name>hadoop.http.authentication.simple.anonymous.allowed</name>
  <value>true</value>
  <description>
    Indicates if anonymous requests are allowed when using 'simple' authentication.
  </description>
</property>

<property>
  <name>hadoop.http.authentication.kerberos.principal</name>
  <value>HTTP/_HOST@LOCALHOST</value>
  <description>
    Indicates the Kerberos principal to be used for HTTP endpoint.
    The principal MUST start with 'HTTP/' as per Kerberos HTTP SPNEGO specification.
  </description>
</property>

<property>
  <name>hadoop.http.authentication.kerberos.keytab</name>
  <value>${user.home}/hadoop.keytab</value>
  <description>
    Location of the keytab file with the credentials for the principal.
    Referring to the same keytab file Oozie uses for its Kerberos credentials for Hadoop.
  </description>
</property>

<!-- HTTP CORS support -->
<property>
  <description>Enable/disable the cross-origin (CORS) filter.</description>
  <name>hadoop.http.cross-origin.enabled</name>
  <value>false</value>
</property>

<property>
  <description>Comma separated list of origins that are allowed for web
    services needing cross-origin (CORS) support. Wildcards (*) and patterns
    allowed</description>
  <name>hadoop.http.cross-origin.allowed-origins</name>
  <value>*</value>
</property>

<property>
  <description>Comma separated list of methods that are allowed for web
    services needing cross-origin (CORS) support.</description>
  <name>hadoop.http.cross-origin.allowed-methods</name>
  <value>GET,POST,HEAD</value>
</property>

<property>
  <description>Comma separated list of headers that are allowed for web
    services needing cross-origin (CORS) support.</description>
  <name>hadoop.http.cross-origin.allowed-headers</name>
  <value>X-Requested-With,Content-Type,Accept,Origin</value>
</property>

<property>
  <description>The number of seconds a pre-flighted request can be cached
    for web services needing cross-origin (CORS) support.</description>
  <name>hadoop.http.cross-origin.max-age</name>
  <value>1800</value>
</property>

<property>
  <name>dfs.ha.fencing.methods</name>
  <value></value>
  <description>
    List of fencing methods to use for service fencing. May contain
    builtin methods (eg shell and sshfence) or user-defined method.
  </description>
</property>

<property>
  <name>dfs.ha.fencing.ssh.connect-timeout</name>
  <value>30000</value>
  <description>
    SSH connection timeout, in milliseconds, to use with the builtin
    sshfence fencer.
  </description>
</property>

<property>
  <name>dfs.ha.fencing.ssh.private-key-files</name>
  <value></value>
  <description>
    The SSH private key files to use with the builtin sshfence fencer.
  </description>
</property>

<property>
  <name>ha.zookeeper.quorum</name>
  <description>
    A list of ZooKeeper server addresses, separated by commas, that are
    to be used by the ZKFailoverController in automatic failover.
  </description>
</property>

<property>
  <name>ha.zookeeper.session-timeout.ms</name>
  <value>5000</value>
  <description>
    The session timeout to use when the ZKFC connects to ZooKeeper.
    Setting this value to a lower value implies that server crashes
    will be detected more quickly, but risks triggering failover too
    aggressively in the case of a transient error or network blip.
  </description>
</property>

<property>
  <name>ha.zookeeper.parent-znode</name>
  <value>/hadoop-ha</value>
  <description>
    The ZooKeeper znode under which the ZK failover controller stores
    its information. Note that the nameservice ID is automatically
    appended to this znode, so it is not normally necessary to
    configure this, even in a federated environment.
  </description>
</property>

<property>
  <name>ha.zookeeper.acl</name>
  <value>world:anyone:rwcda</value>
  <description>
    A comma-separated list of ZooKeeper ACLs to apply to the znodes
    used by automatic failover. These ACLs are specified in the same
    format as used by the ZooKeeper CLI.

    If the ACL itself contains secrets, you may instead specify a
    path to a file, prefixed with the '@' symbol, and the value of
    this configuration will be loaded from within.
  </description>
</property>

<property>
  <name>ha.zookeeper.auth</name>
  <value></value>
  <description>
    A comma-separated list of ZooKeeper authentications to add when
    connecting to ZooKeeper. These are specified in the same format
    as used by the &quot;addauth&quot; command in the ZK CLI. It is
    important that the authentications specified here are sufficient
    to access znodes with the ACL specified in ha.zookeeper.acl.

    If the auths contain secrets, you may instead specify a
    path to a file, prefixed with the '@' symbol, and the value of
    this configuration will be loaded from within.
  </description>
</property>

<!-- Static Web User Filter properties. -->
<property>
  <description>
    The user name to filter as, on static web filters
    while rendering content. An example use is the HDFS
    web UI (user to be used for browsing files).
  </description>
  <name>hadoop.http.staticuser.user</name>
  <value>dr.who</value>
</property>

<!-- SSLFactory configuration -->

<property>
  <name>hadoop.ssl.keystores.factory.class</name>
  <value>org.apache.hadoop.security.ssl.FileBasedKeyStoresFactory</value>
  <description>
    The keystores factory to use for retrieving certificates.
  </description>
</property>

<property>
  <name>hadoop.ssl.require.client.cert</name>
  <value>false</value>
  <description>Whether client certificates are required</description>
</property>

<property>
  <name>hadoop.ssl.hostname.verifier</name>
  <value>DEFAULT</value>
  <description>
    The hostname verifier to provide for HttpsURLConnections.
    Valid values are: DEFAULT, STRICT, STRICT_IE6, DEFAULT_AND_LOCALHOST and
    ALLOW_ALL
  </description>
</property>

<property>
  <name>hadoop.ssl.server.conf</name>
  <value>ssl-server.xml</value>
  <description>
    Resource file from which ssl server keystore information will be extracted.
    This file is looked up in the classpath, typically it should be in Hadoop
    conf/ directory.
  </description>
</property>

<property>
  <name>hadoop.ssl.client.conf</name>
  <value>ssl-client.xml</value>
  <description>
    Resource file from which ssl client keystore information will be extracted
    This file is looked up in the classpath, typically it should be in Hadoop
    conf/ directory.
  </description>
</property>

<property>
  <name>hadoop.ssl.enabled</name>
  <value>false</value>
  <description>
    Deprecated. Use dfs.http.policy and yarn.http.policy instead.
  </description>
</property>

<property>
  <name>hadoop.ssl.enabled.protocols</name>
  <value>TLSv1,SSLv2Hello,TLSv1.1,TLSv1.2</value>
  <description>
    The supported SSL protocols.
  </description>
</property>

<property>
  <name>hadoop.jetty.logs.serve.aliases</name>
  <value>true</value>
  <description>
    Enable/Disable aliases serving from jetty
  </description>
</property>

<property>
  <name>fs.permissions.umask-mode</name>
  <value>022</value>
  <description>
    The umask used when creating files and directories.
    Can be in octal or in symbolic. Examples are:
    "022" (octal for u=rwx,g=r-x,o=r-x in symbolic),
    or "u=rwx,g=rwx,o=" (symbolic for 007 in octal).
  </description>
</property>

<!-- ha properties -->

<property>
  <name>ha.health-monitor.connect-retry-interval.ms</name>
  <value>1000</value>
  <description>
    How often to retry connecting to the service.
  </description>
</property>

<property>
  <name>ha.health-monitor.check-interval.ms</name>
  <value>1000</value>
  <description>
    How often to check the service.
  </description>
</property>

<property>
  <name>ha.health-monitor.sleep-after-disconnect.ms</name>
  <value>1000</value>
  <description>
    How long to sleep after an unexpected RPC error.
  </description>
</property>

<property>
  <name>ha.health-monitor.rpc-timeout.ms</name>
  <value>45000</value>
  <description>
    Timeout for the actual monitorHealth() calls.
  </description>
</property>

<property>
  <name>ha.failover-controller.new-active.rpc-timeout.ms</name>
  <value>60000</value>
  <description>
    Timeout that the FC waits for the new active to become active
  </description>
</property>

<property>
  <name>ha.failover-controller.graceful-fence.rpc-timeout.ms</name>
  <value>5000</value>
  <description>
    Timeout that the FC waits for the old active to go to standby
  </description>
</property>

<property>
  <name>ha.failover-controller.graceful-fence.connection.retries</name>
  <value>1</value>
  <description>
    FC connection retries for graceful fencing
  </description>
</property>

<property>
  <name>ha.failover-controller.cli-check.rpc-timeout.ms</name>
  <value>20000</value>
  <description>
    Timeout that the CLI (manual) FC waits for monitorHealth, getServiceState
  </description>
</property>

<property>
  <name>ipc.client.fallback-to-simple-auth-allowed</name>
  <value>false</value>
  <description>
    When a client is configured to attempt a secure connection, but attempts to
    connect to an insecure server, that server may instruct the client to
    switch to SASL SIMPLE (unsecure) authentication. This setting controls
    whether or not the client will accept this instruction from the server.
    When false (the default), the client will not allow the fallback to SIMPLE
    authentication, and will abort the connection.
  </description>
</property>

<property>
  <name>fs.client.resolve.remote.symlinks</name>
  <value>true</value>
  <description>
      Whether to resolve symlinks when accessing a remote Hadoop filesystem.
      Setting this to false causes an exception to be thrown upon encountering
      a symlink. This setting does not apply to local filesystems, which
      automatically resolve local symlinks.
  </description>
</property>

<property>
  <name>nfs.exports.allowed.hosts</name>
  <value>* rw</value>
  <description>
    By default, the export can be mounted by any client. The value string 
    contains machine name and access privilege, separated by whitespace 
    characters. The machine name format can be a single host, a Java regular 
    expression, or an IPv4 address. The access privilege uses rw or ro to 
    specify read/write or read-only access of the machines to exports. If the 
    access privilege is not provided, the default is read-only. Entries are separated by ";".
    For example: "192.168.0.0/22 rw ; host.*\.example\.com ; host1.test.org ro;".
    Only the NFS gateway needs to restart after this property is updated. 
  </description>
</property>

<property>
  <name>hadoop.user.group.static.mapping.overrides</name>
  <value>dr.who=;</value>
  <description>
    Static mapping of user to groups. This will override the groups if
    available in the system for the specified user. In other words, groups
    look-up will not happen for these users, instead groups mapped in this
    configuration will be used.
    Mapping should be in this format.
    user1=group1,group2;user2=;user3=group2;
    Default, "dr.who=;" will consider "dr.who" as user without groups.
  </description>
</property>

<property>
  <name>rpc.metrics.quantile.enable</name>
  <value>false</value>
  <description>
    Setting this property to true and rpc.metrics.percentiles.intervals
    to a comma-separated list of the granularity in seconds, the
    50/75/90/95/99th percentile latency for rpc queue/processing time in
    milliseconds are added to rpc metrics.
  </description>
</property>

<property>
  <name>rpc.metrics.percentiles.intervals</name>
  <value></value>
  <description>
    A comma-separated list of the granularity in seconds for the metrics which
    describe the 50/75/90/95/99th percentile latency for rpc queue/processing
    time. The metrics are outputted if rpc.metrics.quantile.enable is set to
    true.
  </description>
</property>

<property>
  <name>hadoop.security.crypto.codec.classes.EXAMPLECIPHERSUITE</name>
  <value></value>
  <description>
    The prefix for a given crypto codec, contains a comma-separated
    list of implementation classes for a given crypto codec (eg EXAMPLECIPHERSUITE).
    The first implementation will be used if available, others are fallbacks.
  </description>
</property>

<property>
  <name>hadoop.security.crypto.codec.classes.aes.ctr.nopadding</name>
  <value>org.apache.hadoop.crypto.OpensslAesCtrCryptoCodec, org.apache.hadoop.crypto.JceAesCtrCryptoCodec</value>
  <description>
    Comma-separated list of crypto codec implementations for AES/CTR/NoPadding. 
    The first implementation will be used if available, others are fallbacks.
  </description>
</property>

<property>
  <name>hadoop.security.crypto.cipher.suite</name>
  <value>AES/CTR/NoPadding</value>
  <description>
    Cipher suite for crypto codec.
  </description>
</property>

<property>
  <name>hadoop.security.crypto.jce.provider</name>
  <value></value>
  <description>
    The JCE provider name used in CryptoCodec. 
  </description>
</property>

<property>
  <name>hadoop.security.crypto.buffer.size</name>
  <value>8192</value>
  <description>
    The buffer size used by CryptoInputStream and CryptoOutputStream. 
  </description>
</property>

<property>
  <name>hadoop.security.java.secure.random.algorithm</name>
  <value>SHA1PRNG</value>
  <description>
    The java secure random algorithm. 
  </description>
</property>

<property>
  <name>hadoop.security.secure.random.impl</name>
  <value></value>
  <description>
    Implementation of secure random. 
  </description>
</property>

<property>
  <name>hadoop.security.random.device.file.path</name>
  <value>/dev/urandom</value>
  <description>
    OS security random device file path.
  </description>
</property>

<property>
  <name>hadoop.security.key.provider.path</name>
  <description>
    The KeyProvider to use when managing zone keys, and interacting with
    encryption keys when reading and writing to an encryption zone.
  </description>
</property>

<property>
  <name>fs.har.impl.disable.cache</name>
  <value>true</value>
  <description>Don't cache 'har' filesystem instances.</description>
</property>

<!--- KMSClientProvider configurations -->
<property>
  <name>hadoop.security.kms.client.authentication.retry-count</name>
  <value>1</value>
  <description>
    Number of time to retry connecting to KMS on authentication failure
  </description>
</property>
<property>
  <name>hadoop.security.kms.client.encrypted.key.cache.size</name>
  <value>500</value>
  <description>
    Size of the EncryptedKeyVersion cache Queue for each key
  </description>
</property>
<property>
  <name>hadoop.security.kms.client.encrypted.key.cache.low-watermark</name>
  <value>0.3f</value>
  <description>
    If size of the EncryptedKeyVersion cache Queue falls below the
    low watermark, this cache queue will be scheduled for a refill
  </description>
</property>
<property>
  <name>hadoop.security.kms.client.encrypted.key.cache.num.refill.threads</name>
  <value>2</value>
  <description>
    Number of threads to use for refilling depleted EncryptedKeyVersion
    cache Queues
  </description>
</property>
<property>
  <name>hadoop.security.kms.client.encrypted.key.cache.expiry</name>
  <value>43200000</value>
  <description>
    Cache expiry time for a Key, after which the cache Queue for this
    key will be dropped. Default = 12hrs
  </description>
</property>

 <property>
  <name>ipc.server.max.connections</name>
  <value>0</value>
  <description>The maximum number of concurrent connections a server is allowed
    to accept. If this limit is exceeded, incoming connections will first fill
    the listen queue and then may go to an OS-specific listen overflow queue. 
    The client may fail or timeout, but the server can avoid running out of file
    descriptors using this feature. 0 means no limit.
  </description>
</property>


  <!-- YARN registry -->

  <property>
    <description>
      Is the registry enabled in the YARN Resource Manager?

      If true, the YARN RM will, as needed.
      create the user and system paths, and purge
      service records when containers, application attempts
      and applications complete.

      If false, the paths must be created by other means,
      and no automatic cleanup of service records will take place.
    </description>
    <name>hadoop.registry.rm.enabled</name>
    <value>false</value>
  </property>

  <property>
    <description>
      The root zookeeper node for the registry
    </description>
    <name>hadoop.registry.zk.root</name>
    <value>/registry</value>
  </property>

  <property>
    <description>
      Zookeeper session timeout in milliseconds
    </description>
    <name>hadoop.registry.zk.session.timeout.ms</name>
    <value>60000</value>
  </property>

  <property>
    <description>
      Zookeeper connection timeout in milliseconds
    </description>
    <name>hadoop.registry.zk.connection.timeout.ms</name>
    <value>15000</value>
  </property>

  <property>
    <description>
      Zookeeper connection retry count before failing
    </description>
    <name>hadoop.registry.zk.retry.times</name>
    <value>5</value>
  </property>

  <property>
    <description>
    </description>
    <name>hadoop.registry.zk.retry.interval.ms</name>
    <value>1000</value>
  </property>

  <property>
    <description>
      Zookeeper retry limit in milliseconds, during
      exponential backoff.

      This places a limit even
      if the retry times and interval limit, combined
      with the backoff policy, result in a long retry
      period
    </description>
    <name>hadoop.registry.zk.retry.ceiling.ms</name>
    <value>60000</value>
  </property>

  <property>
    <description>
      List of hostname:port pairs defining the
      zookeeper quorum binding for the registry
    </description>
    <name>hadoop.registry.zk.quorum</name>
    <value>localhost:2181</value>
  </property>

  <property>
    <description>
      Key to set if the registry is secure. Turning it on
      changes the permissions policy from "open access"
      to restrictions on kerberos with the option of
      a user adding one or more auth key pairs down their
      own tree.
    </description>
    <name>hadoop.registry.secure</name>
    <value>false</value>
  </property>

  <property>
    <description>
      A comma separated list of Zookeeper ACL identifiers with
      system access to the registry in a secure cluster.

      These are given full access to all entries.

      If there is an "@" at the end of a SASL entry it
      instructs the registry client to append the default kerberos domain.
    </description>
    <name>hadoop.registry.system.acls</name>
    <value>sasl:yarn@, sasl:mapred@, sasl:hdfs@</value>
  </property>

  <property>
    <description>
      The kerberos realm: used to set the realm of
      system principals which do not declare their realm,
      and any other accounts that need the value.

      If empty, the default realm of the running process
      is used.

      If neither are known and the realm is needed, then the registry
      service/client will fail.
    </description>
    <name>hadoop.registry.kerberos.realm</name>
    <value></value>
  </property>

  <property>
    <description>
      Key to define the JAAS context. Used in secure
      mode
    </description>
    <name>hadoop.registry.jaas.context</name>
    <value>Client</value>
  </property>

  <property>
    <description>
      Enable hdfs shell commands to display warnings if (fs.defaultFS) property
      is not set.
    </description>
    <name>hadoop.shell.missing.defaultFs.warning</name>
    <value>false</value>
  </property>

  <property>
    <name>hadoop.shell.safely.delete.limit.num.files</name>
    <value>100</value>
    <description>Used by -safely option of hadoop fs shell -rm command to avoid
      accidental deletion of large directories. When enabled, the -rm command
      requires confirmation if the number of files to be deleted is greater than
      this limit.  The default limit is 100 files. The warning is disabled if
      the limit is 0 or the -safely is not specified in -rm command.
    </description>
  </property>

  <property>
    <name>fs.client.htrace.sampler.classes</name>
    <value></value>
    <description>The class names of the HTrace Samplers to use for Hadoop
      filesystem clients.
    </description>
  </property>

  <property>
    <name>hadoop.htrace.span.receiver.classes</name>
    <value></value>
    <description>The class names of the Span Receivers to use for Hadoop.
    </description>
  </property>

  <property>
    <description>
      Enable the "/logs" endpoint on all Hadoop daemons, which serves local
      logs, but may be considered a security risk due to it listing the contents
      of a directory.
    </description>
    <name>hadoop.http.logs.enabled</name>
    <value>true</value>
  </property>

  <property>
    <name>fs.client.resolve.topology.enabled</name>
    <value>false</value>
    <description>Whether the client machine will use the class specified by
      property net.topology.node.switch.mapping.impl to compute the network
      distance between itself and remote machines of the FileSystem. Additional
      properties might need to be configured depending on the class specified
      in net.topology.node.switch.mapping.impl. For example, if
      org.apache.hadoop.net.ScriptBasedMapping is used, a valid script file
      needs to be specified in net.topology.script.file.name.
    </description>
  </property>


  <!-- Azure Data Lake File System Configurations -->

  <property>
    <name>adl.feature.override.readahead</name>
    <value>true</value>
    <description>
      Enables read aheads in the ADL client, the feature is used to
      improve read throughput.
      This works in conjunction with the value set in
      adl.feature.override.readahead.max.buffersize.
      When set to false the read ahead feature is turned off.
      Default : True if not configured.
    </description>
  </property>

  <property>
    <name>adl.feature.override.readahead.max.buffersize</name>
    <value>8388608</value>
    <description>
      Define maximum buffer size to cache read ahead data, this is
      allocated per process to
      cache read ahead data. Applicable only when
      adl.feature.override.readahead is set to true.
      Default : 8388608 Byte i.e. 8MB if not configured.
    </description>
  </property>

  <property>
    <name>adl.feature.override.readahead.max.concurrent.connection</name>
    <value>2</value>
    <description>
      Define maximum concurrent connection can be established to
      read ahead. If the data size is less than 4MB then only 1 read n/w
      connection
      is set. If the data size is less than 4MB but less than 8MB then 2 read
      n/w connection
      is set. Data greater than 8MB then value set under the property would
      take
      effect. Applicable only when adl.feature.override.readahead is set
      to true and buffer size is greater than 8MB.
      It is recommended to reset this property if the
      adl.feature.override.readahead.max.buffersize
      is less than 8MB to gain performance. Application has to consider
      throttling limit for the account as well before configuring large
      buffer size.
    </description>
  </property>

  <property>
    <name>fs.adl.impl</name>
    <value>org.apache.hadoop.fs.adl.AdlFileSystem</value>
  </property>

  <property>
    <name>fs.AbstractFileSystem.adl.impl</name>
    <value>org.apache.hadoop.fs.adl.Adl</value>
  </property>

  <property>
    <name>hadoop.caller.context.enabled</name>
    <value>false</value>
    <description>When the feature is enabled, additional fields are written into
      name-node audit log records for auditing coarse granularity operations.
    </description>
  </property>
  <property>
    <name>hadoop.caller.context.max.size</name>
    <value>128</value>
    <description>The maximum bytes a caller context string can have. If the
      passed caller context is longer than this maximum bytes, client will
      truncate it before sending to server. Note that the server may have a
      different maximum size, and will truncate the caller context to the
      maximum size it allows.
    </description>
  </property>
  <property>
    <name>hadoop.caller.context.signature.max.size</name>
    <value>40</value>
    <description>
      The caller's signature (optional) is for offline validation. If the
      signature exceeds the maximum allowed bytes in server, the caller context
      will be abandoned, in which case the caller context will not be recorded
      in audit logs.
    </description>
  </property>

</configuration>