diff --git a/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/security/ShellBasedUnixGroupsMapping.java b/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/security/ShellBasedUnixGroupsMapping.java
index f4db520ac2..d0c4e11cbe 100644
--- a/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/security/ShellBasedUnixGroupsMapping.java
+++ b/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/security/ShellBasedUnixGroupsMapping.java
@@ -215,7 +215,7 @@ private Set<String> getUnixGroups(String user) throws IOException {
           groups = resolvePartialGroupNames(user, e.getMessage(),
               executor.getOutput());
         } catch (PartialGroupNameException pge) {
-          LOG.warn("unable to return groups for user {}", user, pge);
+          LOG.debug("unable to return groups for user {}", user, pge);
           return EMPTY_GROUPS_SET;
         }
       }