[ 
https://issues.apache.org/jira/browse/HDFS-14601?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16897613#comment-16897613
 ] 

Fengnan Li commented on HDFS-14601:
-----------------------------------

During ZKFC launch, it needs to initialize a localTarget which is the namenode 
which runs at the same host this ZKFC runs. Right now this logic is done by 
looping through all namenode hosts, create a socket address and match this 
socket address with the local socket address. This doesn't work with DNS since 
current code will only resolve to one address, which could be the other 
namenode instead of the local one, thus ZKFC wouldn't be able to get a 
localTarget.

We can change the logic to make it work with DNS but I am not sure it is worth 
the effort. [~elgoiri] What's your thought? The code is in 
DFSUtil.java#getSuffixIDs()

 

> NameNode HA with single DNS record for NameNode discovery prevent running ZKFC
> ------------------------------------------------------------------------------
>
>                 Key: HDFS-14601
>                 URL: https://issues.apache.org/jira/browse/HDFS-14601
>             Project: Hadoop HDFS
>          Issue Type: Bug
>            Reporter: Kei Kori
>            Assignee: Fengnan Li
>            Priority: Major
>
> ZKFC seems not treat one DNS record for NameNode discovery as multiple 
> NameNodes, so launching ZKFC is blocked on NameNodes which has only one 
> "dfs.ha.namenodes" definition with DNS for resolving multiple NameNodes.



--
This message was sent by Atlassian JIRA
(v7.6.14#76016)

---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]

Reply via email to