[ https://issues.apache.org/jira/browse/HDFS-2179?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Todd Lipcon resolved HDFS-2179. ------------------------------- Resolution: Fixed Fix Version/s: HA branch (HDFS-1623) Hadoop Flags: [Reviewed] > HA: namenode fencing mechanism > ------------------------------ > > Key: HDFS-2179 > URL: https://issues.apache.org/jira/browse/HDFS-2179 > Project: Hadoop HDFS > Issue Type: Sub-task > Components: name-node > Reporter: Todd Lipcon > Assignee: Todd Lipcon > Fix For: HA branch (HDFS-1623) > > Attachments: hdfs-2179.txt, hdfs-2179.txt, hdfs-2179.txt > > > In an HA cluster, when there are two NNs, the invariant that only one NN is > active at a time has to be preserved in order to prevent "split brain > syndrome." Thus, when a standby NN is transition to "active" state during a > failover, it needs to somehow _fence_ the formerly active NN to ensure that > it can no longer perform edits. This JIRA is to discuss and implement NN > fencing. -- This message is automatically generated by JIRA. For more information on JIRA, see: http://www.atlassian.com/software/jira