diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/resources/hdfs-default.xml b/hadoop-hdfs-project/hadoop-hdfs/src/main/resources/hdfs-default.xml
index 96c04f0ba4..4caee9e76f 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/resources/hdfs-default.xml
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/resources/hdfs-default.xml
@@ -1811,8 +1811,8 @@
dfs.namenode.stale.datanode.interval
30000
- Default time interval for marking a datanode as "stale", i.e., if
- the namenode has not received heartbeat msg from a datanode for
+ Default time interval in milliseconds for marking a datanode as "stale",
+ i.e., if the namenode has not received heartbeat msg from a datanode for
more than this time interval, the datanode will be marked and treated
as "stale" by default. The stale interval cannot be too small since
otherwise this may cause too frequent change of stale states.