<html><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><br><br><div class="gmail_quote">On Sat, Nov 21, 2009 at 3:25 PM, Andreas Dilger <span dir="ltr"><<a href="mailto:adilger@sun.com" target="_blank">adilger@sun.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;"> <div>On 2009-11-20, at 19:36, Dam Thanh Tung wrote:<br> <blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;"> We just started drbd from OST (which has been rebuild RAID partition) and connect with drbd on an working OST. Everything was fine and the synchronization completed without any error report. But, when we mount this backup OST in to our system, some of web client can't connect to it ( MDS and some others can ) and after a short time, in that OST message log, we see many error report like this :<br> <br> Nov 19 19:59:36 OST6 kernel: LDISKFS-fs error (device drbd6): ldiskfs_lookup: unlinked inode 159588368 in dir #261333022<br> <br> Nov 19 19:59:36 OST6 kernel: LustreError: 3893:0:(filter_lvb.c:90:filter_lvbo_init()) lustre-OST0006: bad object 996598/0: rc -2<br> </blockquote> <br></div> It sounds to me like you are trying to mount the "backup OST" at the same time as the "primary OST"? That is definitely NOT how Lustre works. You should stop that, as it will cause serious filesystem corruption if you are doing that.<br> <br> The backup OST should only be mounted when the primary has failed (preferably when the primary is powered down via STONITH so that there is no chance it will still modify the filesystem). This is normally controlled by HA software like Heartbeat or similar.</blockquote> <div><br>Thank you for your fast reply, Andreas<br><br>Maybe because i explained not really clearly, so you are misunderstanding me. <br><br>I only mounted our backup OST when my primary OST went down, and it showed me those error report <br> </div><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;"><div><br> <blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;"> In order to using drbd as back up solution as i described above, do we need to reformat disk before synchronize data or just sync it directly?<br> <br> </blockquote> <br></div> I haven't used DRBD myself, but I believe that it should NOT require formatting a device before using DRBD on it. However, there would need to be an initial synchronization to copy all of the data from the primary copy to the backup. DRBD is just doing a block-level copy of one device to another, it doesn't know anything about the filesystem.<br> <br></blockquote><div>If i don't need to re-format before synchronizing data,could you please tell me why did we have those error? The synchronization completed successfully ! ( we synchronize data from primary OST to backup OST, i when i mount the backup OST, get those errors - our primary OST contains data but it can't connect to our MDS, because of it, we have to use backup OST like i described <a href="http://lists.lustre.org/pipermail/lustre-discuss/attachments/20091118/5b0a96ce/attachment-0001.html"></a><a href="http://lists.lustre.org/pipermail/lustre-discuss/attachments/20091118/5b0a96ce/attachment-0001.html">before in this list</a> )<br> <br>Everything is going worse and worse. Hope you can help me bring the data back. If you need more information, i'll send you in detail. <br><br>Many thanks <br><br> <br></div><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;"> Cheers, Andreas<br><font color="#888888"> --<br> Andreas Dilger<br> Sr. Staff Engineer, Lustre Group<br> Sun Microsystems of Canada, Inc.<br> <br> </font></blockquote></div><br></body></html>