[
https://issues.apache.org/jira/browse/HDFS-14118?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16736811#comment-16736811
]
Fengnan Li commented on HDFS-14118:
-----------------------------------
Tested below two cases:
1) set up 2 routers pointing to the same NN, and set up one DNS host name
pointing to the ips of these two routers, give the client the domain name, when
one of the router fails, the client is able to failover to access the left
router.
2) for the hdfs ha, set up one DNS host name pointing to IPs of active and
standby NN, set the `dfs.client.failover.random.order` to be true to make it
possible for the client to run into standby NN first. The client can be able to
successfully failover to the active NN after the standby remote exception.
> RBF: Use DNS to help resolve routers
> ------------------------------------
>
> Key: HDFS-14118
> URL: https://issues.apache.org/jira/browse/HDFS-14118
> Project: Hadoop HDFS
> Issue Type: Sub-task
> Reporter: Fengnan Li
> Assignee: Fengnan Li
> Priority: Major
> Attachments: HDFS-14118.patch
>
>
> Clients will need to know about routers to talk to the HDFS cluster
> (obviously), and having routers updating (adding/removing) will have to make
> every client change, which is a painful process.
> DNS can be used here to resolve the single domain name clients knows to a
> list of routers in the current config. However, DNS won't be able to consider
> only resolving to the working router based on certain health thresholds.
> There are some ways about how this can be solved. One way is to have a
> separate script to regularly check the status of the router and update the
> DNS records if a router fails the health thresholds. In this way, security
> might be carefully considered for this way. Another way is to have the client
> do the normal connecting/failover after they get the list of routers, which
> requires the change of current failover proxy provider.
--
This message was sent by Atlassian JIRA
(v7.6.3#76005)
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
