Brandon Li created HDFS-5587:
--------------------------------
Summary: add debug information when NFS fails to start with
duplicate user or group names
Key: HDFS-5587
URL: https://issues.apache.org/jira/browse/HDFS-5587
Project: Hadoop HDFS
Issue Type: Bug
Components: nfs
Reporter: Brandon Li
Assignee: Brandon Li
When the host provides duplicate user or group names, NFS will not start and
print errors like the following:
{noformat}
... ...
13/11/25 18:11:52 INFO nfs3.Nfs3Base: registered UNIX signal handlers for
[TERM, HUP, INT]
Exception in thread "main" java.lang.IllegalArgumentException: value already
present: s-iss
at com.google.common.base.Preconditions.checkArgument(Preconditions.java:115)
at com.google.common.collect.AbstractBiMap.putInBothMaps(AbstractBiMap.java:112)
at com.google.common.collect.AbstractBiMap.put(AbstractBiMap.java:96)
at com.google.common.collect.HashBiMap.put(HashBiMap.java:85)
at org.apache.hadoop.nfs.nfs3.IdUserGroup.updateMapInternal(IdUserGroup.java:85)
at org.apache.hadoop.nfs.nfs3.IdUserGroup.updateMaps(IdUserGroup.java:110)
at org.apache.hadoop.nfs.nfs3.IdUserGroup.<init>(IdUserGroup.java:54)
at
org.apache.hadoop.hdfs.nfs.nfs3.RpcProgramNfs3.<init>(RpcProgramNfs3.java:172)
at
org.apache.hadoop.hdfs.nfs.nfs3.RpcProgramNfs3.<init>(RpcProgramNfs3.java:164)
at org.apache.hadoop.hdfs.nfs.nfs3.Nfs3.<init>(Nfs3.java:41)
at org.apache.hadoop.hdfs.nfs.nfs3.Nfs3.main(Nfs3.java:52)
13/11/25 18:11:54 INFO nfs3.Nfs3Base: SHUTDOWN_MSG:
... ...
{noformat}
The reason NFS should not start is that, HDFS (non-kerberos cluster) uses name
as the only way to identify a user. On some linux box, it could have two users
with the same name but different user IDs. Linux might be able to work fine
with that most of the time. However, when NFS gateway talks to HDFS, HDFS
accepts only user name. That is, from HDFS' point of view, these two different
users are the same user even though they are different on the Linux box.
The duplicate names on Linux systems sometimes is because of some legacy system
configurations, or combined name services.
Regardless, NFS gateway should print some help information so the user can
understand the error and the remove the duplicated names before NFS restart.
--
This message was sent by Atlassian JIRA
(v6.1#6144)
