Bob Ball wrote: > Is there a recommended way to migrate an MDT (MGS is separate) volume > from one location to another on the same server? This uses iSCSI volumes. > > Lustre 1.8.4
We have recently migrated our MDT to an new volume to change the inode size. We used tar and getfattr/setfattr for this closely following the MDT backup and restore procedure from the manual. We did take our file system down completely for over a week over Christmas to do this, though it could have possibly been quicker if we had not taken time off as well. We also did very careful checking of everything before bringing up the new MDT. This was on a file system with at that time about 90M files. Be sure to use a tar version that has an efficient way to detect files that are completely sparse. We found that the version on RHEL5 did not have this and taking backups took very long, I think there is a thread on the list about this which has a link to a fixed tar version for RHEL5 which we used in the end. Also, we did not use any --posix or --xattr option for tar as we found that this is broken and creates bogus files. We used plain 'tar --sparse'. If you don't have to change any mkfs options (like inode size in our case), I suspect any block based copy mechanism like dd or pvmove is the better option, possibly followed by a resize. Good luck, Frederik -- Frederik Ferner Computer Systems Administrator phone: +44 1235 77 8624 Diamond Light Source Ltd. mob: +44 7917 08 5110 (Apologies in advance for the lines below. Some bits are a legal requirement and I have no control over them.) -- This e-mail and any attachments may contain confidential, copyright and or privileged material, and are for the use of the intended addressee only. If you are not the intended addressee or an authorised recipient of the addressee please notify us of receipt by returning the e-mail and do not use, copy, retain, distribute or disclose the information in or attached to the e-mail. Any opinions expressed within this e-mail are those of the individual and not necessarily of Diamond Light Source Ltd. Diamond Light Source Ltd. cannot guarantee that this e-mail or any attachments are free from viruses and we cannot accept liability for any damage which you may sustain as a result of software viruses which may be transmitted in or with the message. Diamond Light Source Limited (company no. 4375679). Registered in England and Wales with its registered office at Diamond House, Harwell Science and Innovation Campus, Didcot, Oxfordshire, OX11 0DE, United Kingdom _______________________________________________ Lustre-discuss mailing list [email protected] http://lists.lustre.org/mailman/listinfo/lustre-discuss
