PVG Strict Mirroring with alternate link

[zap_2]

Hi Unix Gurus,
I have planned to make new vg that called vg05 with PVG Strict Mirroring Policy and alternate link that have 6 disks as follows :
/dev/dsk/c2t0d0
/dev/dsk/c4t1d1
/dev/dsk/c4t1d3
/dev/dsk/c4t1d0
/dev/dsk/c2t0d1
/dev/dsk/c2t0d3
How to create alternate link for couple of disks such as :
/dev/dsk/c2t0d0 & /dev/dsk/c4t1d0
/dev/dsk/c2t0d1 & /dev/dsk/c4t1d3
/dev/dsk/c2t0d3 & /dev/dsk/c4t1d1


If I want to create :
vg05 with 3 pvg as follow:
pvg1 : /dev/dsk/c2t0d0 & /dev/dsk/c4t1d3
pvg2 : /dev/dsk/c2t0d1 & /dev/dsk/c4t1d1
pvg3 : /dev/dsk/c2t0d3 & /dev/dsk/c4t1d0

lvol1:PVG-strict mirroring use pvg1 mount /u04
lvol2:PVG-strict mirroring use pvg2 mount /u05
lvol3:PVG-strict mirroring use pvg3 mount /u06

Please tell me step by step because of I am newbie using LVM and mirror diskux.Any replies will be appreciated.Thanks ...

[Florian Heigl (new acc)]

Hey there :)

I'm a bit confused:

- the alternate link for
/dev/dsk/c4t1d1 should be /dev/dsk/c2t1d1

while
pvg1 : /dev/dsk/c2t0d0 & /dev/dsk/c4t1d3
are completely different devices (which is ok, of course, but the alternate links are not in Your list)

I'll try to outline the steps (and my guesses) in the second post.

[Florian Heigl (new acc)]

/etc/lvmpvg should read:

VG /dev/vg05
PVG PVG1
/dev/dsk/c2t0d0
/dev/dsk/c4t0d0
/dev/dsk/c2t1d3
/dev/dsk/c4t1d3
PVG PVG2
/dev/dsk/c2t0d1
/dev/dsk/c4t0d1
/dev/dsk/c4t1d1
/dev/dsk/c2t1d1
PVG PVG3
/dev/dsk/c2t0d3
/dev/dsk/c4t0d3
/dev/dsk/c4t1d0
/dev/dsk/c2t1d0

then vgcreate /dev/vg05 /dev/dsk/c2t0d0 /dev/dsk/c4t0d0 ...

THE BAD NEWS IS: You won't achieve what You want, because PVG-strict mirroring is meaning to mirror between two different PVGs..., so data in PVG1 gets mirrored to PVG2.

To my understanding You should create only two PVGs, each containing 3PVs and their alternate paths.
- creating standard vg (vgcreate -s 256 -p 32 -e 5000 /dev/vg05 /dev/dsk/...
edit /etc/lvmpvg
then
lvcreate -s g -l 1 /dev/vg05
lvextend -L /dev/vg05/lvol1

If You really, really need to contain data like it was in your original plan, I think You need to create three VGs.

Sorry this has not become really clear & easy :>

[Tim D Fulford]

Why are you trying to use 3 PVG's!! To use PVG strict you mus have two PVGs as PVGa --> PVGb

I'm also confused about your primary and alternate links and what disks are available, so

/etc/lvmpvg
VG /dev/vg05
PVG primary
/dev/dsk/c2t0d0
/dev/dsk/c4t0d1
/dev/dsk/c2t0d3
/dev/dsk/c4t0d0 # alt lnk to c2t0d0
/dev/dsk/c2t0d1 # alt lnk to c4t0d1
/dev/dsk/c4t0d3 # alt lnk to c2t0d3
PVG mirror
/dev/dsk/c4t1d0
/dev/dsk/c2t1d1
/dev/dsk/c4t1d3
/dev/dsk/c2t1d0 # alt lnk to c4t1d0
/dev/dsk/c4t1d1 # alt lnk to c2t1d1
/dev/dsk/c2t1d3 # alt lnk to c4t1d3

To do teh actual mirroring
lvcreate -D y -s g -m 1 -n -L vg05

Regards

Tim