[linux-lvm] shift PV from disk to raid device?

[Kai Schaetzl]

Stuart D. Gathman wrote on Tue, 9 Dec 2008 11:54:08 -0500 (EST):

Hallo, thanks for the suggestions. I'll try to follow that logically and with 
possible commands, see below with comments/questions.

> 1) remove sda from md2 array

mdadm /dev/md2 --fail /dev/sda3 --remove /dev/sda3

> 2) use dd or pvremove to clear PV info in md2.  This should not
>    affect sda since sda is removed from md2

md2 shouldn't have PV info. do you mean sdb3? (this would destroy my data on 
sdb3 then), so:

vgchange dom0 -an (deactivate the LVs on sdb3)
pvremove /dev/sdb3 ?
After this point a pvdisplay should show /dev/sda3 as the active PV for dom0.
(At the moment I get: "using /dev/sdb3 not /dev/sda3")

> 3) pvcreate md2 as a new PV and add to volume group

pvcreate /dev/md2
I fear I will get "device busy", not? (just a feeling from recent experience 
with juggling with md and lvm that are on top of each other)
vgextend dom0 /dev/md2
(dom0 then consists of sda3 and md2)

> 4) pvmove sda -> md2.  The data should physically go on sdb, or whatever the
>    other mirror of md2 is.

ok

> 5) check that all LVs are gone from sda, and remove from volume group

vgreduce dom0 /dev/sda

> 6) pvremove sda

ok

> 7) add sda to md2 array, and synchronize.

ok

Did I get it so far correctly? What about (2) (3) where I'm not sure?



Kai

-- 
Kai Schätzl, Berlin, Germany
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