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Vinayakumar B commented on HDFS-5889: ------------------------------------- Sounds good nicholas. > When rolling upgrade is in progress, standby NN should create checkpoint for > downgrade. > --------------------------------------------------------------------------------------- > > Key: HDFS-5889 > URL: https://issues.apache.org/jira/browse/HDFS-5889 > Project: Hadoop HDFS > Issue Type: Sub-task > Components: namenode > Reporter: Tsz Wo (Nicholas), SZE > Assignee: Tsz Wo (Nicholas), SZE > > After rolling upgrade is started and checkpoint is disabled, the edit log may > grow to a huge size. It is not a problem if rolling upgrade is finalized > normally since NN keeps the current state in memory and it writes a new > checkpoint during finalize. However, it is a problem if admin decides to > downgrade. It could take a long time to apply edit log. Rollback does not > have such problem. -- This message was sent by Atlassian JIRA (v6.1.5#6160)