1831645 Members
1983 Online
110029 Solutions
New Discussion

mirrored disk size

 
SOLVED
Go to solution
andi_1
Frequent Advisor

mirrored disk size

Hi guys,

Suppose, I have the following information:

--- Volume groups ---
VG Name /dev/vg00
VG Write Access read/write
VG Status available
Max LV 255
Cur LV 8
Open LV 8
Max PV 16
Cur PV 1
Act PV 1
Max PE per PV 2500
VGDA 2
PE Size (Mbytes) 4
Total PE 1023
Alloc PE 1019
Free PE 4
Total PVG 0
Total Spare PVs 0
Total Spare PVs in use 0

--- Physical volumes ---
PV Name /dev/dsk/c11t5d0
PV Status available
Total PE 1023
Free PE 4

Am I correct assuming that /dev/dsk/c11t5do belongs to vg00.

Also, given the above information how do I know how much is mirrored? What field should I look for?

Thank you.
11 REPLIES 11
Clemens van Everdingen
Honored Contributor

Re: mirrored disk size

Hi,

Correct, that disk belongs to vg00.
But as far as I can see there is only one disk, so meaning that vg00 is not mirrored at all.

C.
The computer is a great invention, there are as many mistakes as ever, but they are nobody's fault !
andi_1
Frequent Advisor

Re: mirrored disk size

Clemens,

Thank you for your reply. So, assuming there are two disks, it means vg00 was mirrored over two disks?

Thanks!
Sandip Ghosh
Honored Contributor

Re: mirrored disk size

Do lvdisplay -v /dev/vg00 |more
to see which disk is mirrored with whom.

Sandip
Good Luck!!!
andi_1
Frequent Advisor

Re: mirrored disk size

Hi,

I cannot do lvdisplay. This is information coming from the customer server, which I don't have access to.


So, I have to figure out based on the information provided.
Helen French
Honored Contributor

Re: mirrored disk size

Hi,

1) Yes, The disk belongs to vg00. A better way to check this can be:

# pvdisplay -v /dev/dsk/cxtydz

2) Mirroring is done at the LV level not at the VG level. You have to check the 'lvdisplay -v' to findout the mirror status of the lV:

# lvdisplay -v /dev/vgxx/lvolx

HTH,
Shiju
Life is a promise, fulfill it!
S.K. Chan
Honored Contributor

Re: mirrored disk size

There are a few ways of determine if vg00 is mirrored. Take for instance if you got 2 disks in vg00 (you know this from vgdisplay -v vg00), to confirm if they are mirrored or not you can run ..

# lvlnboot -v

Doing ..

# lvdisplay -v /dev/vg00/lvolX | more

on each individual LVs in vg00 will give you details (if they are mirrored) how those LVs are distributed over which disk.
Helen French
Honored Contributor
Solution

Re: mirrored disk size

Hi Leon:

Just by seeing 2 disks in vg00 ( or in any VG) doesn't mean that the disks are mirrored.

If you are talking about software mirror with Mirror/UX, then you can see the information from 'lvdisplay' command. If you are using a disk array/hardware mirror, then you can check the array status.

HTH,
Shiju
Life is a promise, fulfill it!
Clemens van Everdingen
Honored Contributor

Re: mirrored disk size

Hi,

vgdisplay -v /dev/vg00 should show that the volume group contains one or more disks.
If more than one, you should do as lvdisplay to see if these are mirror's of each other.

C.
The computer is a great invention, there are as many mistakes as ever, but they are nobody's fault !
Sandip Ghosh
Honored Contributor

Re: mirrored disk size

First you ask your customer to do lvdisplay -v /dev/vg00/lv*|more to see what it is saying as Mirror Copies. If it says 1 , that means it is mirrored. If it is saying 0 that means it is not mirrored.

If you could see 1 then oyu can do with -v option to see which physical disks are there in the mirrored partition.

Sandip
Good Luck!!!
Patrick Wallek
Honored Contributor

Re: mirrored disk size

With this particular VG00, there is no way it can be mirrored. There is only 1 disk in this VG.

The first things to look at are the CUR PV and the ACT PV. Both of these are 1 on this VG, so there is no other disk to mirror to.

Michael Tully
Honored Contributor

Re: mirrored disk size

Only other thing to add, and to echo Sanjay is that if there was a second disk, and you feel it should be there it would shown in the vgdisplay output as a mirrored disk as 'stale'
Anyone for a Mutiny ?