[
https://issues.apache.org/jira/browse/HDFS-6648?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15939252#comment-15939252
]
Zhe Zhang commented on HDFS-6648:
---------------------------------
[~chris.douglas] Looks like the release note needs to be updated? Thanks.
> Order of namenodes in ConfiguredFailoverProxyProvider is undefined
> ------------------------------------------------------------------
>
> Key: HDFS-6648
> URL: https://issues.apache.org/jira/browse/HDFS-6648
> Project: Hadoop HDFS
> Issue Type: Bug
> Components: ha, hdfs-client
> Affects Versions: 2.7.0
> Reporter: Rafal Wojdyla
> Assignee: Inigo Goiri
> Fix For: 2.9.0
>
> Attachments: HDFS-6648-000.patch, HDFS-6648-001.patch
>
>
> In org.apache.hadoop.hdfs.server.namenode.ha.ConfiguredFailoverProxyProvider,
> in the constructor, there's a map <nameservice : < service-id :
> service-rpc-address > > (DFSUtil.getHaNnRpcAddresses). It's a LinkedHashMap
> of HashMaps. The order is kept for _nameservices_. Then to find active
> namenode, for nameservice, we get HashMap of <service-id :
> service-rpc-address > for requested nameservice (taken from URI request), And
> for this HashMap we get values - order of this collection is not strictly
> defined! In the code:
> {code}
> Collection<InetSocketAddress> addressesOfNns = addressesInNN.values();
> {code}
> And then we put these values (in not defined order) into ArrayList of
> proxies, and then in getProxy we start from first proxy in the list and
> failover to next if needed.
> It would make sense for ConfiguredFailoverProxyProvider to keep order of
> proxies/namenodes defined in hdfs-site.xml.
--
This message was sent by Atlassian JIRA
(v6.3.15#6346)
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
