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Colin Patrick McCabe commented on HDFS-4173: -------------------------------------------- bq. so this would cause the NN to initialize the shared edits dir on standby startup, wouldn't it? There's an "if" statement like this: {code} if (u.getScheme().equals(NNStorage.LOCAL_URI_SCHEME)) { ... } else { // format } {code} Since the NFS shared edits directory has a LOCAL_URI_SCHEME (it's a path, after all), it won't be affected by this change. The question of whether the SNN and NN will both try to auto-format the same (QJM-managed) {{JournalNode}} quorum when starting up for the first time is more concerning. We could hook into {{FSEditLog#initJournalsForWrite}}. In HA mode, that only gets called later, when a NN becomes active. > If the NameNode has already been formatted, but a QuroumJournal has not, > auto-format it on startup > -------------------------------------------------------------------------------------------------- > > Key: HDFS-4173 > URL: https://issues.apache.org/jira/browse/HDFS-4173 > Project: Hadoop HDFS > Issue Type: Improvement > Components: journal-node, name-node > Affects Versions: 2.0.3-alpha > Reporter: Colin Patrick McCabe > Assignee: Colin Patrick McCabe > Priority: Minor > Attachments: HDFS-4173.001.patch > > > If we have multiple edit log directories, and some of them are formatted, but > others are not, we format the unformatted ones. However, when we implemented > QuorumJournalManager, we did not extend this behavior to it. It makes sense > to do this. > One use case is if you want to add a QuorumJournalManager URI > ({{journal://}}) to an existing {{NameNode}}, without reformatting > everything. There is currently no easy way to do this, since {{namenode > \-format}} will nuke everything, and there's no other way to format the > {{JournalNodes}}. -- This message is automatically generated by JIRA. If you think it was sent incorrectly, please contact your JIRA administrators For more information on JIRA, see: http://www.atlassian.com/software/jira