If the journal is lost, the OSD is lost. This can be a problem if you use 1 SSD for journals for many OSDs. There has been some discussion about making the OSDs able to recover from a lost journal, but I haven't heard anything else about it. I haven't been paying much attention to the developer mailing list though. For your second question, I'd start by looking at the source code in src/osd/ReplicatedPG.cc (for standard replication), or src/osd/ECBackend.cc (for Erasure Coding). I'm not a Ceph developer though, so that might not be the right place to start. On Tue, Aug 12, 2014 at 7:08 PM, yuelongguang <fastsync at 163.com> wrote: > hi,all > > 1. > can osd start up if journal is lost and it has not been replayed? > > 2. > how it catchs up latest epoch? take osd as example, where is the code? > it better you consider journal is lost or not. > in my mind journal only includes meta/R/W operations, does not include > data(file data). > > > thanks > > > > _______________________________________________ > ceph-users mailing list > ceph-users at lists.ceph.com > http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com > > -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.ceph.com/pipermail/ceph-users-ceph.com/attachments/20140813/33c6070e/attachment.htm>
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