[
https://issues.apache.org/jira/browse/HDFS-14118?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16755542#comment-16755542
]
Íñigo Goiri commented on HDFS-14118:
------------------------------------
{quote}
I'm not sure if we need any new config in core-default.xml for now, since we
are not adding the implementation. How about we just keep the config (e.g.,
RESOLVE_SERVICE_KEY) in hdfs-default.xml and only move the related code to
commons?
{quote}
I'd like to have a self contained entity in commons including:
* Interface for resolving
* Implementation of the resolver with DNS
* Utility to create a new resolver using {{config#getClass}} and
{{ReflectionUtils#newInstance()}}
* Simple unit test for the resolver including the mock (this would use the
utility to create the new resolver and test that it outputs the mocked values)
To do this, we need a key to set the impl of the resolver.
> Use DNS to resolve Namenodes and Routers
> ----------------------------------------
>
> Key: HDFS-14118
> URL: https://issues.apache.org/jira/browse/HDFS-14118
> Project: Hadoop HDFS
> Issue Type: New Feature
> Reporter: Fengnan Li
> Assignee: Fengnan Li
> Priority: Major
> Attachments: DNS testing log, HDFS-14118.001.patch,
> HDFS-14118.002.patch, HDFS-14118.003.patch, HDFS-14118.004.patch,
> HDFS-14118.005.patch, HDFS-14118.006.patch, HDFS-14118.007.patch,
> HDFS-14118.008.patch, 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: hdfs-issues-unsubscr...@hadoop.apache.org
For additional commands, e-mail: hdfs-issues-h...@hadoop.apache.org
