On Fri, 2007-04-27 at 07:53 +1000, James C. McPherson wrote: > Ming Zhang wrote: > > On Fri, 2007-04-27 at 09:25 +1200, Ian Collins wrote: > >> Claus Guttesen wrote: > >> > >>> Hi. > >>> > >>> If I create a zpool with the following command: > >>> > >>> zpool create tank raidz2 da0 da1 da2 da3 da4 da5 da6 da7 > >>> > >>> and after a reboot the device names for some reason are changed so da2 > >>> and da5 are swapped, either by altering the LUN setting on the storage > >>> or by switching cables/swapping disks etc.? > >>> > >>> How will zfs handle that? Will it simply acknowledge that all devices > >>> are present and the pool is intact and report online or will it > >>> complain? > >>> > >> It will just work. > > > > one thing i would guess is that the device id will keep the same and be > > used as final proof while path name is only used as a clue. > > > > can somebody confirm this? thx. > > > Yes, this works. We make use of the device id (which > doesn't change, for almost all circumstances) to identify > luns and route read and write ops appropriately. > > > The only circumstance that I am aware of where a devid might > change is if a disk or tape's firmware is changed such that > its SCSI INQUIRY page83 response changes. This is a very rare > thing and you the user would have to knowingly kick this off. >
as Eric pointed out, i think at last the on disk data will help to validate them. thx. > > cheers, > James C. McPherson > -- > Solaris kernel software engineer, system admin and troubleshooter > http://www.jmcp.homeunix.com/blog > Find me on LinkedIn @ http://www.linkedin.com/in/jamescmcpherson _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
