Alejandro Fernandez created AMBARI-12488:
--------------------------------------------
Summary: RU - Use haadmin failover command instead of killing ZKFC
during upgrade/downgrade
Key: AMBARI-12488
URL: https://issues.apache.org/jira/browse/AMBARI-12488
Project: Ambari
Issue Type: Story
Components: ambari-server
Affects Versions: 2.0.0
Reporter: Alejandro Fernandez
Assignee: Alejandro Fernandez
Fix For: 2.1.2
Currently RU orchestration during upgrade/downgrade kills ZKFC on the active
NameNode to initiate a failover to standby. We should instead use the failover
command.
E.g.,
{code}
su hdfs -c 'hdfs haadmin -failover nn1 nn2'
{code}
Where nn1 is the current namenode if it if the active one, and nn2 is the
remaining namenode.
This is safer than killing zkfc on the active namenode because this command
first tries to gracefully transition a NameNode to the Standby state. If this
fails, the fencing methods (as configured by dfs.ha.fencing.methods) will be
attempted until one succeeds. After this process the second NameNode will be
transitioned to the Active state.
It reduces long waits between ZKFC kill, failure kicking-in after a timeout,
and then NN becoming active.
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
