topic Re: Expanding / (root) filesytem in Operating System - HP-UX

Expanding / (root) filesytem

Rafael Casero — Wed, 05 Apr 2006 22:13:24 GMT

I currently have 78 gigs available on my disk, my / partition is 200 MG's I'm currently running out of space often. I would like to know.

1. What's the best practice to extend / partition.

2. Should I expand it to the full 78 gigs, and would it cause performance issues?

...I'm fairly new to the UNIX Environment...

Thanks...

Re: Expanding / (root) filesytem

Arunvijai_4 — Wed, 05 Apr 2006 22:38:33 GMT

Hi Rafael,

You can check these threads for more information,

http://forums1.itrc.hp.com/service/forums/questionanswer.do?threadId=97821&admit=-682735245+1144294574992+28353475
http://forums1.itrc.hp.com/service/forums/questionanswer.do?threadId=505209

Basically, Ignite your using make_tape_recovery, boot to console, Re-ignite your machine with desired size of / (root) partition.

-Arun

Re: Expanding / (root) filesytem

YoungHwan, Ko — Wed, 05 Apr 2006 23:31:51 GMT

Hi Rafael..

If your system configured lvol4, you cannot resize / file system.
To increase / size, use make_tape_recovery.
and resize / .
# make_tape_recovery -Av

# shutdown -ry 0

System reboot..

Main Menu: Enter command or menu > sea

Path# Device Path (dec) Device Path (mnem) Device Type Rev
----- ----------------- ------------------ ----------- ----
P0 0/0/3/0.0 media.0 Random access media 1
P1 0/1/1/0.1 intscsia.1 Random access media 1
P2 0/1/1/0.0 intscsia.0 Random access media 1

Main Menu: Enter command or menu > bo P# --> Tape Device

Have a nice day..

Re: Expanding / (root) filesytem

Raj D. — Thu, 06 Apr 2006 00:16:42 GMT

Ragael,

For expanding root (/) , you have to take ignite backup of vg00 , and while restoring , you have option to expand it.

End option to take all backup of your system and reinstall it , with a new root filesystem size.

Cheers,
Raj.

Re: Expanding / (root) filesytem

Raj D. — Thu, 06 Apr 2006 00:16:52 GMT

Rafael,

For expanding root (/) , you have to take ignite backup of vg00 , and while restoring , you have option to expand it.

End option to take all backup of your system and reinstall it , with a new root filesystem size.

Cheers,
Raj.

Re: Expanding / (root) filesytem

Antonio Cardoso_1 — Thu, 06 Apr 2006 01:16:56 GMT

Rafael,

you should first consider why / is running out of space.
- run bdf to list all filesystems
- run du -sk on each directory of / which isn't a filesystem (from bdf output)

An alternative to extend this filesystem may be to move some of those directories from / to another filesystem: link them to new location.

Re: Expanding / (root) filesytem

Tiziano Contorno _ — Thu, 06 Apr 2006 04:02:50 GMT

"/" filesyste should be well "confined", no new files should go directly into it, except the root history file updates, cde preferences files, mozilla files, etc. This make "/" pretty "static".

Run this command to see which are the largest and newest file you have in "/" alone.

du -ks $(find / -type f -mtime -30 -xdev) | sort -n

This can help you identify why you are going low on space.

Regards.

Re: Expanding / (root) filesytem

Tiziano Contorno _ — Thu, 06 Apr 2006 04:12:24 GMT

There's also an other way to extend root filesystem that is quite complex.

Supposing a 2 internal disks configuration, all vg00 LVs mirrored.

1) fsadm on /tmp (and lvreduce /tmp) as many MBs as you need for root fs;
2) extend root logical volume and extend its filesystem;
3) extend back to the desired value /tmp

This is due to "/" filesystem being in contiguos and strict allocation policy.

Regards.

Re: Expanding / (root) filesytem

MarkSyder — Thu, 06 Apr 2006 08:20:40 GMT

It is seldom necessary to expand /.

I suspect you've either got a process writing to root that would be better writing to a filesystem of its own or a backup writing to a non-existent device. This is quite common: what happens is a typo in the device name when you run a backup command resulting in a large file in the /dev/rmt directory. Check this before taking the drastic (and usually unnecessary) action of increasing /.

Mark Syder (like the drink but spelt different)

Re: Expanding / (root) filesytem

Emil Velez — Fri, 07 Apr 2006 07:27:15 GMT

I have a possible solution for you but it utilizes some advanced LVM commands and requires you to really understand your disk layout. Do not try this without fully understanding this and thinking it through.

Lets assume you have 2 disks in vg00 one with the boot area and the / filesystem and the other with other filesystems but with sufficient room.

On your boot disk /dev/dsk/c1t15d0 you have

lvol1
lvol2
lvol3
lvol4
lvol5

Lvol3 cannot be extended since / needs to be contiguous and lvol4 is in the way.

if you have 2 disks in vg00
examples /dev/dsk/c1t15d0 and /dev/dsk/c2t15d0 and the 2nd disk has some room.

you can do the following

pvmove -n /dev/vg00/lvol4 /dev/dsk/c1t15d0 /dev/dsk/c3t15d0

this will move lvol4 to the other disk providing a hole for the / filesystem.

Then you can do the following
lvextend -L 200 /dev/vg00/lvol3 (assuming you have that space)
fsadm -F vxfs -b 200M /
(to extend the filesystem.. This assumes onlinejfs)

Then you can move lvol4 back to the disk..
pvmove -n /dev/vg00/lvol4 /dev/dsk/c3t15d0 /dev/dsk/c1t15d0

good luck..

Re: Expanding / (root) filesytem

Rafael Casero — Fri, 07 Apr 2006 10:28:41 GMT

Thanks all for your quik response. Can any tell me the command to see if the disk are raid 5 or mirror ?

Re: Expanding / (root) filesytem

Arunvijai_4 — Fri, 07 Apr 2006 10:50:49 GMT

Hi Rafael,

If you have Veritas installed, you can find it out using # vxprint -ht

-Arun