dd if=/dev/rdsk/c1t2d0 of=/dev/rdsk/c2t2d0 bs=2048

[Joe Profaizer]

If I did a pvremove on /dev/rdsk/c2t2d0 before I initiated the dd command (in subject line), would the "dd" still complete correctly or do I need the LVM structure to reside on the physical volume of the "of"?

Thanks,

..Joe

[James R. Ferguson]

Hi Joe:

You toasted the disk as an LVM disk when you did the 'pvremove'. Since the 'dd' is simply a bit-for-bit copy it will (still) complete OK. The question, however, is once the copy completes, what do you expect to do and to have?

Regards!

...JRF...

[Joe Profaizer]

I just wanted to "dd" the system disk, take the "of" target disk into our test system and boot it. Basically wanted to replicate a system disk and boot a like server from it.

[S.K. Chan]

Why would you need to run dd after a pvmove ? Are you pvmoving on
=>a VG that's in a shared mode ?
=>LVs that are striped ?
Because if you do that would explain why you need to run dd afterwards though I'm not sure if it'll work. Pvmove works best on a "regular" or "normal" logical volumes. If for some reason you need to run dd, you would still need to vgexport the physical volumes and vgimport it back with the new disks specified.

[Joe Profaizer]

pvremove not pvmove

[S.K. Chan]

Sorry ... sometimes the eyes can play trick on you ..
Like JRF said, the LVM info/config on the disk is gone if you run pvremove. The dd should copy the LVM header back onto the disk for you (I've never tested this ..).

[James R. Ferguson · Accepted solution]

Hi Joe:

If you want to put things "right", move the physical disk back to its original server and do a 'vgcfgrestore' of its LVM header. Then, do a 'dd' as before.

Regards!

...JRF..

[A. Clay Stephenson]

When you do your new dd, increase your bs to something like =64k (or even 1024k); the transfer will go much faster. Also, make sure that you specify only bs= (as opposed to ibs= obs=) to avoid double buffering with a copy between them.

[Joe Profaizer]

I forgot the "k" after 2048 in my message. Thanks anyway.