[ https://issues.apache.org/jira/browse/HBASE-2312?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Todd Lipcon updated HBASE-2312: ------------------------------- Fix Version/s: (was: 0.90.1) 0.90.2 > Possible data loss when RS goes into GC pause while rolling HLog > ---------------------------------------------------------------- > > Key: HBASE-2312 > URL: https://issues.apache.org/jira/browse/HBASE-2312 > Project: HBase > Issue Type: Bug > Components: master, regionserver > Affects Versions: 0.90.0 > Reporter: Karthik Ranganathan > Assignee: Nicolas Spiegelberg > Priority: Critical > Fix For: 0.90.2 > > > There is a very corner case when bad things could happen(ie data loss): > 1) RS #1 is going to roll its HLog - not yet created the new one, old one > will get no more writes > 2) RS #1 enters GC Pause of Death > 3) Master lists HLog files of RS#1 that is has to split as RS#1 is dead, > starts splitting > 4) RS #1 wakes up, created the new HLog (previous one was rolled) and > appends an edit - which is lost > The following seems like a possible solution: > 1) Master detects RS#1 is dead > 2) The master renames the /hbase/.logs/<regionserver name> directory to > something else (say /hbase/.logs/<regionserver name>-dead) > 3) Add mkdir support (as opposed to mkdirs) to HDFS - so that a file > create fails if the directory doesn't exist. Dhruba tells me this is very > doable. > 4) RS#1 comes back up and is not able create the new hlog. It restarts > itself. -- This message is automatically generated by JIRA. - For more information on JIRA, see: http://www.atlassian.com/software/jira