[
https://issues.apache.org/jira/browse/HADOOP-8247?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13250296#comment-13250296
]
Hari Mankude commented on HADOOP-8247:
--------------------------------------
bq.Hi Hari. That's specifically the point of the FORCEMANUAL flag. It is not
safe to use it with automatic failover. So, the user has to accept the warning
and acknowledge they're about to do something dumb, that will break auto
failover if the ZKFCs are running.
If there is such a significant element of danger in using FORCEMANUAL with
unforseen consequences and possibilities such as data corruption and even worse
HA state, is this command option useful? There are always admins who disregard
these warnings. Instead, wouldn't it be better to come up with a set of
procedures to unwedge the cluster, starting with setting auto-failover key to
false, resetting NNs and using manual failover?
> Auto-HA: add a config to enable auto-HA, which disables manual FC
> -----------------------------------------------------------------
>
> Key: HADOOP-8247
> URL: https://issues.apache.org/jira/browse/HADOOP-8247
> Project: Hadoop Common
> Issue Type: Improvement
> Components: auto-failover, ha
> Affects Versions: Auto Failover (HDFS-3042)
> Reporter: Todd Lipcon
> Assignee: Todd Lipcon
> Attachments: hadoop-8247.txt, hadoop-8247.txt, hadoop-8247.txt,
> hadoop-8247.txt
>
>
> Currently, if automatic failover is set up and running, and the user uses the
> "haadmin -failover" command, he or she can end up putting the system in an
> inconsistent state, where the state in ZK disagrees with the actual state of
> the world. To fix this, we should add a config flag which is used to enable
> auto-HA. When this flag is set, we should disallow use of the haadmin command
> to initiate failovers. We should refuse to run ZKFCs when the flag is not
> set. Of course, this flag should be scoped by nameservice.
--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators:
https://issues.apache.org/jira/secure/ContactAdministrators!default.jspa
For more information on JIRA, see: http://www.atlassian.com/software/jira
