As part of a SAN migration, I had to move an LDOM’s boot disk from one SAN to another. These notes begin from a point where the new LUNs are presented to the box and properly multipathed. The old LUN is 36Gb, and pretty full, so I’ve been given 145Gb for the new one, and I want to use all of it.
In this example the domain is called
Looking at the existing boot disk from inside the domain I see:
# iostat -En c0d0 Soft Errors: 0 Transport Errors: 0 Protocol Errors: 0 Vendor: SUN Product: VDSK Size: 39.02GB <39018823680 bytes>
There’s no reference to the SAN or those long multipathed target names because the disk is abstracted by the primary domain via the virtual disk server. What we need to do is add the new LUN to the VDS so it’s visible in the domain. Then, from the domain we can attach the new disk to the old one as a mirror, let them sync, and remove the original mirror.
So, in the global, map the LUN’s device to a virtual disk. Remember (I
often forget) that you need the path to the full disk device, including
/dev/dsk, and the
# ldm add-vdsdev /dev/dsk/c5t600601600DC02D0048F57258A29EE111d0s2 mydom-newboot@primary-vds
Then map the disk to the VDS
# ldm add-vdisk mydom-newboot mydom-newboot@primary-vds mydom
And tell the domain that’s the new boot disk
# ldm set-variable boot-device=mydom-newboot mydom
Connect to the domain, and the disk should show up in
you even needing to do a
Because this is a root pool you have to attach slice 0 of an SMI
labelled disk. If you have an EFI label, use
format -e to change it,
and make a slice 0 at least as large as the one you’re attaching to.
As I said earlier, my new device is bigger than my old one, and I want to use the new space. So I set
# zpool set autoexpand=on rpool
and attach my new LUN.
# zpool attach rpool c0d0s0 c0d1s0
Wait for the resilver to complete and check the size:
# zpool get size rpool NAME PROPERTY VALUE SOURCE rpool size 36.2G -
Then detach the original half of the mirror and see if anything’s changed
# zpool detach rpool c0d0s0 # zpool get size rpool NAME PROPERTY VALUE SOURCE rpool size 145G -
And, if you have the luxury of being able to do so, reboot-test it. You can never be too careful!
Back in the primary we have to clear up the references to the original
boot device. You can see the disk in
ldm ls-bindings and the device in
# ldm ls-bindings mydom | grep boot auto-boot\?=true boot-device=mydom-newboot mydom-newboot mydom-newboot@primary-vds disk@1 primary # ldm rm-vdisk mydom-boot mydom # ldm ls-services | grep boot primary-vds primary mydom-boot /dev/dsk/c5t60060480000290101683533030344142d0s2 # ldm rm-vdsdev mydom-boot@primary-vds
And we’re done. Making the box forget the LUNs is an exercise for another day, and exactly how you do it depends on the drivers and multipathing software you use.