On Thu, Jul 14, 2016 at 1:42 AM, txm <chunquanbijiasuo@xxxxxxx> wrote: > I am a user of cephfs. > > Recently i met a problem by using the cephfs-journal-tool. > > There were some strange things happened below. > > 1.After use the cephfs-journal-tool and cephfs-table-tool(i came up with the "negative object nums” issues, so i tried these tools to repair the cephfs)，i remount the cephfs. > 2.Then i found that the old data(a directoy and a file under it) is missing. > 3.But after i create a new file at the root of cephfs, the missing directory show up. Then i delete the new created file,the “missing directory” disappeared soon. > 4.So this is the problem, when i create something under the root of cephfs, the missing directory show up, when i delete it ,the “missing directory” disappeared. > > Here is my question: > 1. I am not sure whether this damage is caused by cephfs-journal-tool? > 2. If so, another question is , how this damage came up by using the cephfs-journal-tool and what should i do next to fix this problem? > > Apparently ,i didn’t lose my data, but this is strange after all. cephfs-journal-tool mucks about directly with CephFS' raw storage and it is definitely possible to break things in strange ways. In your case, it sounds like you zapped your journal without flushing it out to the backing objects (or using the scavenge dentries functionality which tries to make that unnecessary in the case when your MDS won't start). It's not surprising that in some cases you are getting the data back as you look at different versions of your (slightly-inconsistent) data structures. Basically, you used disaster recovery tools in a not-disaster-recovery situation, and you used them improperly. :( Fixing it probably requires some surgery. Steps would be to figure out where the "missing directory" is stored (and isn't) and then probably to remove it from everywhere and re-create as needed. -Greg _______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
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