hadoop-hdfs-issues mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Vinayakumar B (JIRA)" <j...@apache.org>
Subject [jira] [Updated] (HDFS-7714) Simultaneous restart of HA NameNodes and DataNode can cause DataNode to register successfully with only one NameNode.
Date Mon, 09 Feb 2015 05:13:35 GMT

     [ https://issues.apache.org/jira/browse/HDFS-7714?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]

Vinayakumar B updated HDFS-7714:
--------------------------------
    Attachment: HDFS-7714-002.patch

Thanks [~cnauroth].
I can see that only {{TestBPOfferService.testNNsFromDifferentClusters}} was failed due to
this change.
Others seems to mess-up with some other cluster

Anyway, removed isAlive() changes. Kept only EOFException approach.

> Simultaneous restart of HA NameNodes and DataNode can cause DataNode to register successfully
with only one NameNode.
> ---------------------------------------------------------------------------------------------------------------------
>
>                 Key: HDFS-7714
>                 URL: https://issues.apache.org/jira/browse/HDFS-7714
>             Project: Hadoop HDFS
>          Issue Type: Bug
>          Components: datanode
>    Affects Versions: 2.6.0
>            Reporter: Chris Nauroth
>            Assignee: Vinayakumar B
>         Attachments: HDFS-7714-001.patch, HDFS-7714-002.patch
>
>
> In an HA deployment, DataNodes must register with both NameNodes and send periodic heartbeats
and block reports to both.  However, if NameNodes and DataNodes are restarted simultaneously,
then this can trigger a race condition in registration.  The end result is that the {{BPServiceActor}}
for one NameNode terminates, but the {{BPServiceActor}} for the other NameNode remains alive.
 The DataNode process is then in a "half-alive" state where it only heartbeats and sends block
reports to one of the NameNodes.  This could cause a loss of storage capacity after an HA
failover.  The DataNode process would have to be restarted to resolve this.



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)

Mime
View raw message