topic Re: Adding swap in Operating System - HP-UX

Adding swap

Andreas Voss — Wed, 19 Dec 2001 15:35:51 GMT

Hi,

i have a system with mirrored vg00 (2 x 4GB)and have to increase swap but there is not enough space in vg00.
So i bought two additional disks (4GB) and put them into my HASS enclosure. These new disk should also be mirrored.

Now i'm not sure how to add the swap.
Should i add the disks into vg00 (vgextend)
or
create a new vg and add them there ?

Kind Regards

Andreas

Re: Adding swap

Jeff Machols — Wed, 19 Dec 2001 15:40:31 GMT

you can only extend the current vol if it can be contiguous. If not you will have to create a new LV. Just use the swapon command for this (it will require a reboot though).

man 1m swapon

Re: Adding swap

Mark Greene_1 — Wed, 19 Dec 2001 15:41:25 GMT

check here:

http://docs.hp.com/cgi-bin/fsearch/framedisplay?top=/hpux/onlinedocs/B2355-90672/B2355-90672_top.html&con=/hpux/onlinedocs/B2355-90672/00/00/63-con.html&toc=/hpux/onlinedocs/B2355-90672/00/00/63-toc.html&searchterms=swap%7cadding&queryid=20011219-074426

Re: Adding swap

Rita C Workman — Wed, 19 Dec 2001 15:45:48 GMT

It can be a 6 of one half dozen of the other...but for myself. I tend to set the second set of disks as part of vg00 and then define a good size lvol for swap. That way in a pinch I can still extend something in vg (if I have to buy time) before getting the next set of disks to add..

Just my way of doing things,
Rita

Re: Adding swap

Sanjay_6 — Wed, 19 Dec 2001 15:46:54 GMT

Hi andrea,

Try this link,

http://us-support2.external.hp.com/cki/bin/doc.pl/sid=06441d351602b8f346/screen=ckiDisplayDocument?docId=200000056198282

http://us-support2.external.hp.com/cki/bin/doc.pl/sid=06441d351602b8f346/screen=ckiDisplayDocument?docId=200000053039597

Hope this helps.

Regds

Re: Adding swap

S.K. Chan — Wed, 19 Dec 2001 15:47:04 GMT

I would create a separate vg for it. After that you can do this to create your addl swap.

# lvcreate -L 400 -n swap2 -C y -r n /dev/vg01
==> create 400MB contigous lv called swap in vg01 with bad block reallocation turned off

# swapon -p 1 /dev/vg01/swap2
==> enable swap with priority 1.

# swapinfo -ta
==> check to see if added swap is enabled.

# vi /etc/fstab
....
/dev/vg01/swap2 ... swap pri=1 0 1
....

Re: Adding swap

Uday_S_Ankolekar — Wed, 19 Dec 2001 15:48:05 GMT

Hi,
Hi
I would create new VG and than use priority

The following doc might useful

http://us-support2.external.hp.com/cki/bin/doc.pl/sid=c13f35fc11a4d6f7e3/screen=ckiDisplayDocument?docId=200000053039597
-USA..

Re: Adding swap

Helen French — Wed, 19 Dec 2001 15:48:18 GMT

hey,

If you are looking for a secondary swap space, then you can create a new VG, then create new lv and mirror it. U can add this new lv as the new swap space.

There is no problem in adding this to vg00 and doing the same thing.

Shiju

Re: Adding swap

Steven Gillard_2 — Wed, 19 Dec 2001 15:53:27 GMT

My advice would be to add the volumes to vg00, because then you can use the swap vols as dump volumes as well with lvlnboot. I'd also leave as much free space on the disks as possible as its always good to have some available in vg00.

Regards,
Steve

Re: Adding swap

Thierry Poels_1 — Wed, 19 Dec 2001 16:21:40 GMT

hi,

let's start a fight about this ;-)
Personally I don't think it really matters if you create a new Volume Group or add them to VG00; it's up to you, your habbits, company policy, whatever,... Both have some advantages and disadvantages, but no real winner or loser on both.

But if you add them to VG00, make sure the new swap space resides completely on the new disk, or that a different swap priority is assigned. You really do not want to round-robbin between swap spaces on the same disk ;-)

good luck,
Thierry.