[jira] Commented: (HADOOP-6121) High Availability support for Hadoop

["Steve Loughran (JIRA)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/HADOOP-6121?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12726067#action_12726067 ] 

Steve Loughran commented on HADOOP-6121:
----------------------------------------

The JobTracker can persist its state, but for HA you'd need to do failover in the clients- currently to achieve that you need to switch the replacement to the same hostname/IP address of the original.

The issue of HA for HDFS is raised in HDFS-243

> High Availability support for Hadoop
> ------------------------------------
>
>                 Key: HADOOP-6121
>                 URL: https://issues.apache.org/jira/browse/HADOOP-6121
>             Project: Hadoop Common
>          Issue Type: New Feature
>          Components: dfs, mapred
>            Reporter: Jie Qiu
>
> Currently, We look at the HA of Hadoop cluster. We need to consider the NameNode HA as well as Jobtracker HA. For NameNode, we want to build primary/standy or master-slaves pattern to provide NameNode HA. Therefore, we need to consider how to ship log between primary/standby/slaves and how commit "write" operation to NameNode after the agreement among primary/standby/slaves on log. Whether will we use Linux HA package or NameNode-built-in HA package without the help of outter Linux HA package. 
> After NameNode become high availability, is it necessary to provide HA for Jobtracker? Can Jobtracker  persist the states of Jobs and tasks into HA NameNode? Or Jobtracker also needs the same approach from NameNode for HA support.

-- 
This message is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.