[jira] [Commented] (HBASE-18226) Disable reverse DNS lookup at HMaster and use default hostname provided by RegionServer

["Esteban Gutierrez (JIRA)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/HBASE-18226?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16052530#comment-16052530 ] 

Esteban Gutierrez commented on HBASE-18226:
-------------------------------------------

[~onpduo], can you please elaborate more how can this help other deployments without Ambari? I think modifying /etc/hosts is a terrible way to address this problem. The RS should be provided via gethostname or not at all. If Ambari or any other configuration management tool doesn't support providing the desired hostname for a configuration that we already have, that means that those configuration management tools should add a way to support our feature instead of HBase providing a workaround for a missing feature from those tools. Thanks.

> Disable reverse DNS lookup at HMaster and use default hostname provided by RegionServer
> ---------------------------------------------------------------------------------------
>
>                 Key: HBASE-18226
>                 URL: https://issues.apache.org/jira/browse/HBASE-18226
>             Project: HBase
>          Issue Type: Bug
>            Reporter: Duo Xu
>         Attachments: HBASE-18226.001.patch
>
>
> This JIRA is to address the similar problem as HBASE-12954, but there are some little differences,
> 1. HBASE-12954 provides the configuration "hbase.regionserver.hostname" so users can configure it on every regionserver with preferred hostnames. However, this configuration cannot be set through Ambari because each regionserver has a different value of this setting.
> 2. In Azure HDInsight clusters, we want to give each RegionServer/workernode a FQDN by modifying /etc/hosts on that node, then when regionserver starts, 
> {code}
> String hostName = shouldUseThisHostnameInstead() ? useThisHostnameInstead :
>       rpcServices.isa.getHostName();
> {code}
> it uses FQDN names here but on HMaster side, it will do reverse DNS lookup which cannot be resolved.
> {code}
>  // if regionserver passed hostname to use,
>  // then use it instead of doing a reverse DNS lookup
>  ServerName rs = master.getServerManager().regionServerStartup(request, ia);
> {code}
> My proposed fix is to add a new configuration "*hbase.regionserver.hostname.auto*". If it is set to true, then Regionserver will use the value returned by *rpcServices.isa.getHostName()* as the hostname overwriting whatever users specifies in "*hbase.regionserver.hostname*" and send to HMaster. HMaster will not do reverse DNS lookup, which has been implemented in HBASE-12954. If users want to provide their own hostnames in "*hbase.regionserver.hostname*", "*hbase.regionserver.hostname.auto*" must be false.
> I will submit a patch later today.



--
This message was sent by Atlassian JIRA
(v6.4.14#64029)