On 01/22/09 08:22, Alexandre Chartre wrote: > On 01/16/09 10:21, Tom Gendron wrote: >> >> Liam Merwick wrote: >>> On 16/01/2009 15:29, Tom Gendron wrote: >>> >>>> Hi, >>>> >>>> I am playing with the warm migration feature of ldm 1.1 and notice that >>>> there is no provision made to move the root disk from source to target >>>> machine. I must do this by some external means correct? >>>> >>>> >>> Yes, the disk backend(s) must be visible to both machines. e.g. a SAN or >>> have the disk image files exported via NFS. >>> >>> >> I see how NFS could do this but I am confused on how to do it with my >> SAN. I have direct attached fiber channel disks that are visible to >> both hosts but I am not sure how to share the file system. ZFS is going >> to label the pool and be tied to one of the hosts. I would have to >> explicitly export it and then import it to the target machine. Is there >> a filesystem solution to this with native Solaris tools? I think QFS >> would solve this but that is not native. Anything else? > > With a SAN, you directly export a LUN as a virtual disk, and the guest > domain will use that disk. Then you can use ZFS or whatever filesystem > from the guest domain.
Hi Alex, just a clarification regarding the file system on the LUN. Via a statement, although really a question :) Any single writer file system can be used as the file system on the LUN. The source domain will initially be reading and writing to the LUN, while during the migration the target domain will be reading only (if at all), thus there is no issue of file system cache conflicts. Once the source domain has been suspended completely, the target domain takes full control of the LUN. So whether the file system in the LUN is UFS or ZFS, there is no concern about lack of file system cache mismatch. >> How are we planning to solve this when we complete the migration >> capability as in live migration? > > We plan to support more types of storage, like ZFS in some future version > of migration. Basically a zpool will be initially imported on the source This is the case where the boot or data devices are vdevs or files on ZFS, which is separate from whether ZFS is the file system as understood by the OS running in the guest domain. (I am trying to differentiate how Tom's question could be interpreted--how I am trying to distinguish my interpretations of it! ) Thanks Steffen > system, then when the target domain is suspended the zpool will be exported > from the target system and imported on the source system. Finally the domain > will be resumed on the target system. So the zpool will be automatically > migrated during the migration by using a zpool export/import. > > alex.
