Todd Lipcon created HDFS-4025: --------------------------------- Summary: QJM: Sychronize past log segments to JNs that missed them Key: HDFS-4025 URL: https://issues.apache.org/jira/browse/HDFS-4025 Project: Hadoop HDFS Issue Type: Sub-task Components: ha Affects Versions: QuorumJournalManager (HDFS-3077) Reporter: Todd Lipcon Assignee: Todd Lipcon
Currently, if a JournalManager crashes and misses some segment of logs, and then comes back, it will be re-added as a valid part of the quorum on the next log roll. However, it will not have a complete history of log segments (i.e any individual JN may have gaps in its transaction history). This mirrors the behavior of the NameNode when there are multiple local directories specified. However, it would be better if a background thread noticed these gaps and "filled them in" by grabbing the segments from other JournalNodes. This increases the resilience of the system when JournalNodes get reformatted or otherwise lose their local disk. -- 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