hadoop-hdfs-issues mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Arpit Agarwal (JIRA)" <j...@apache.org>
Subject [jira] [Commented] (HDFS-8277) Safemode enter fails when Standby NameNode is down
Date Sat, 09 May 2015 02:29:00 GMT

    [ https://issues.apache.org/jira/browse/HDFS-8277?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14536124#comment-14536124

Arpit Agarwal commented on HDFS-8277:

Hi [~brahmareddy], you are right and that is part of the fix. It does not address the main
issue that the administrator's intention is not preserved across failover and restart. Even
a successful command guarantees nothing since failover just a few seconds later could put
the filesystem back in read-write mode.

>From a brief offline chat with [~sanjay.radia] and [~cnauroth] - the agreement was that
manual safe mode transitions must be logged in NN persistent storage. We'll need edit log
entries for manual safe mode transitions and a flag in the FsImage. [~surendrasingh], do you
want to take a crack at fixing it as part of this jira? I'd be happy to help if you get stuck.

> Safemode enter fails when Standby NameNode is down
> --------------------------------------------------
>                 Key: HDFS-8277
>                 URL: https://issues.apache.org/jira/browse/HDFS-8277
>             Project: Hadoop HDFS
>          Issue Type: Bug
>          Components: ha, HDFS, namenode
>    Affects Versions: 2.6.0
>         Environment: HDP 2.2.0
>            Reporter: Hari Sekhon
>            Assignee: surendra singh lilhore
>            Priority: Minor
>         Attachments: HDFS-8277.patch, HDFS-8277_1.patch, HDFS-8277_2.patch, HDFS-8277_3.patch,
> HDFS fails to enter safemode when the Standby NameNode is down (eg. due to AMBARI-10536).
> {code}hdfs dfsadmin -safemode enter
> safemode: Call From nn2/x.x.x.x to nn1:8020 failed on connection exception: java.net.ConnectException:
Connection refused; For more details see:  http://wiki.apache.org/hadoop/ConnectionRefused{code}
> This appears to be a bug in that it's not trying both NameNodes like the standard hdfs
client code does, and is instead stopping after getting a connection refused from nn1 which
is down. I verified normal hadoop fs writes and reads via cli did work at this time, using
nn2. I happened to run this command as the hdfs user on nn2 which was the surviving Active
> After I re-bootstrapped the Standby NN to fix it the command worked as expected again.

This message was sent by Atlassian JIRA

View raw message