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Vinay commented on HDFS-5504: ----------------------------- Thanks Jing for the review and commit > In HA mode, OP_DELETE_SNAPSHOT is not decrementing the safemode threshold, > leads to NN safemode. > ------------------------------------------------------------------------------------------------ > > Key: HDFS-5504 > URL: https://issues.apache.org/jira/browse/HDFS-5504 > Project: Hadoop HDFS > Issue Type: Bug > Components: snapshots > Affects Versions: 3.0.0, 2.2.0 > Reporter: Vinay > Assignee: Vinay > Fix For: 2.3.0 > > Attachments: HDFS-5504.patch, HDFS-5504.patch > > > 1. HA installation, standby NN is down. > 2. delete snapshot is called and it has deleted the blocks from blocksmap and > all datanodes. log sync also happened. > 3. before next log roll NN crashed > 4. When the namenode restartes then it will fsimage and finalized edits from > shared storage and set the safemode threshold. which includes blocks from > deleted snapshot also. (because this edits is not yet read as namenode is > restarted before the last edits segment is not finalized) > 5. When it becomes active, it finalizes the edits and read the delete > snapshot edits_op. but at this time, it was not reducing the safemode count. > and it will continuing in safemode. > 6. On next restart, as the edits is already finalized, on startup only it > will read and set the safemode threshold correctly. > But one more restart will bring NN out of safemode. -- This message was sent by Atlassian JIRA (v6.1#6144)