Paging space mirror on AIX 5.2 ml3

[rondebbs]

Hello,

Yesterday we had two paging spaces - hd6 and paging02. The hd6 is mirrored on hdisk0 and hdisk1 using rootvg and paging02 was mirrored on hdisk422 and hdisk423 using pagingvg. Today I doubled the size of paging02 to 7689MB. I then added a new page space called paging00 on hdisk422 (it is in pagingvg).

I want to mirror the new paging00 on hdisk422 to hdisk423. I'm not sure of the best way to do this. I have used mirrorvg before when mirroring an entire disk to a new empty disk.

It seems like I would use copylv to copy the partitions in paging00 to hdisk423. Looking at the man page for cplv this does not look possible.

Any suggestions on the best way to handle this either with smit or a command (please provide syntax for command)?

Below is the info on my paging spaces. You can see that hdisk423 has 120 fewer partitions on it than hdisk422. This is because I need to copy the 120 PPs of paging00 to hdisk423.

root@wfscr05:/#lsps -a
Page Space Physical Volume Volume Group Size
paging00 hdisk422 pagingvg 7680MB
paging02 hdisk422 pagingvg 7680MB
hd6 hdisk0 rootvg 3200MB

root@wfscr05:/#lsvg -p pagingvg
pagingvg:
PV_NAME PV STATE TOTAL PPs FREE PPs
hdisk422 active 542 302
hdisk423 active 542 422

root@wfscr05:/#lsvg -l pagingvg
pagingvg:
LV NAME TYPE LPs PPs PVs LV STATE
paging02 paging 120 240 2 open/sy
paging00 paging 120 120 1 open/sy
root@wfscr05:/#

 

[p5wizard]

First off, it is better to have all PgSp's the same size, so if your rootvg still allows it, you should increase hd6 also.

Then, the command for mirroring an LV (whatever the contents) is mklvcopy, not cplv, which is to copy a LV from one VG to another VG.

See the man page for mklvcopy.

[tt]mklvcopy paging00 2[/tt]

Your VG only has 2 PVs so there's no need to specify anything other as to where it should place the mirror copies

HTH,

p5wizard

 

[unixfreak]

Also, mirrorvg would do it as well, mirror remaining non-mirrored LVs. And... AIX doesn't mirror disks, it mirrors LVs! Important distinction!

 

[khalidaaa]

You can create a mirrored lv (or in your case page space) when defining the lv by choosing 2 copies and 2 hdisks in the smitty menu!

Regards,
Khalid

 

[rondebbs]

Guys, thanks all for good info. The mklvcopy worked like a charm.

I will increase hd6 later. Am I correct in assuming that I can do this with users and apps online.

Thanks again - Brad

 

[khalidaaa]

Yes!

http://publib.boulder.ibm.com/infoc...topic=/com.ibm.aix.cmds/doc/aixcmds1/chps.htm

Regards,
Khalid

 

[khalidaaa]

Some other good to know things:

http://www.pcs-computing.com/support/aix_paging_space.html

Regards,
Khalid

 

[MoreFeo]

Just a question,

I've seen you already have a paging space on hdisks 422 and 423 (paging02), adn you've added a new paging space on the same hdisks (paging00 on hdisks 422 and 423).

I'm not sure but I think I've read somewhere that, from a performance point of view it's better not to have several paging spaces on the same disk.

Can anyone confirm this, or tell me if I'm wrong?

 

[unixfreak]

No, you're right about that, they really should be seperate