Add space to / HP UX

[My_Server]

Please I need to add space to my / partition ,If some one have a documentation please can you tell me ?

thank's in advanced

[Steven E. Protter]

Shalom,

First, see if there is stuff there that does not belong.

There should be almost no files, just folders on which filesystems are mounted.

Root fs must be contiguous. You can not add space to it on the end of the disk.

There is a way out though.

Use Ignite.

make_tape_recovery or make_net_recovery

Boot the system off the image and intervene when prompted and restore the system with a larger root parition.

Please indicate whether you have a tape drive or not that is HP made and can be used to boot the system.

There is plenty of detailed instructions on http://docs.hp.com

You need to indicate whether the system is Itanium or PA-RISC.

SEP

[Hein van den Heuvel]

SEP has a great reply as usual, but pay extra attention to his opening line.
'stuff that does not belong there'.

WHY do you think you need to add space to / ?

To put (more) stuff there which does not belong there?
Keep it clean! OS only.
So much easier for the backups.

As soon as you put any extra stuff there, it may grow out of control and cause lack of space on / for critical files.

Invest your time in figuring out what it there, and how to maintain it (archiving and purging logs as needed).

Good luck,
Hein van den Heuvel
HvdH Performance Consulting

[Bill Hassell]

Rethink the requirement to extend the / directory. The only way to add more space is to reload your ENTIRE vg00 volume group using Ignite/UX. This is non-trivial and something you should have practiced before on a test server. There are specific considerations about disk mirroring, alternate disk I/O links, etc.

If you do not manage disk usage in the / directory, you will NEVER be able to make the / directory big enough. The / directory is static, that is, it never changes UNLESS mistakes are made. So 150 to 400 megs is more than enough, even for a 64 processor 128Gb RAM Superdome system. The reason is that there is nothing but:

/etc (rnge 40Mb to 130 Mb)
/sbin (range 40Mb to 150Mb)
/dev

Now the first 2 are the largest directories in /, and /dev is the the smallest at less than 150Kb.

Now many sysadmins are not aware that / is the WORST possible location for root's $HOME (notwithstanding HP and Sun and other flavors defaulting to /). There should be NO regular files in / so start by moving root's $HOME directory. The simplest is to mkdir /root, then move all regular files to /root:

umask 022
mkdir /root

To find regular files:

ls -al / | grep ^-

Now that all the regular files have been moved, there may be some dot-directories such as .elm, .sw and/or .ssh so move those to /root. Now get rid of junk and temp files, and move any files that belong in /var/tmp.

Next, start analyzing / for space (never look for BIG files):

du -kx / | sort -rn | head -15

This listing shows the biggest directories which must be /sbin and /etc. No other directories should be larger than these two. Occasionally, a sysadmin will misspell a tape device file and instead, a massively large mistake file will be in /dev, specifically /dev/rmt. There must be NO regular files in /dev:

find /dev -type f

If there are, move or remove them. If there are any directories similar or larger in size compared to /etc or /sbin, this directory must be moved to /var/tmp. You can deal with that directory later.

Do not allow developers or DBAs to store anything in /. (of course, they can't because / has 755 permission and they won't have root permissions, right?)

So all this is to point out the steps you need to follow to keep / under control. Or you can reload your vg00 from a new Ignite backup tape.

[Geoff Wild]

If you have a spare disk in your system, it is possible to extend root. The following is not for the faint of heart - as always, make sure you have a good backup and ignite image.


No outage required , if you have online jfs.
If you do not have online jfs , do all the following in LVM maintenance mode.
Note: this will only work if SWAP is NOT the next lvol after /

a. Login as root.
b. Find out a free disk / un mirror the rootvg and make that disk free.
c. find out the next logical volume after lvol3(assumed lvol3 is root)
d. pvmove that logical volume onto the newly added disk
[ pvmove -n /dev/vg00/lvol4 /dev/dsk/CURRENT /dev/dsk/NEW]
e. now you should be able to increase root filesystem to an additional `size_of_the_lvol4`.
f. pvmove the lvol4 back to root vg ( vg00)

boot,swap and root are the only lvols that needs a contegeous policy. so , it does not matter where lvol4 is.

Example, move lvol4 away from lvol3 , thus creating a contegeous space right after lvol3. If you need more space on "/" you will be able to move lvol5 ...6 to the next disk and do the stuff. Do remember to migrate them back to the original disk.

Now, if you have mirrored root vg, then break the mirror before you do this.


Practical Example (actual test)

# bdf |grep vg00
/dev/vg00/lvol3 204800 151616 53184 74% /
/dev/vg00/lvol1 125808 49064 64160 43% /stand
/dev/vg00/lvol7 4194304 2501208 1680472 60% /var
/dev/vg00/lvol6 3145728 1856304 1279456 59% /usr
/dev/vg00/lvol5 524288 160992 361104 31% /tmp
/dev/vg00/lvol4 2097152 1833496 261656 88% /opt
/dev/vg00/lvol8 1048576 622656 422632 60% /home
/dev/vg00/lvol10 2097152 1270980 774595 62% /app


Find a spare disk:

strings /etc/lvmtab |grep c7t0d6
pvcreate -f /dev/rdsk/c7t0d6
vgextend /dev/vg00 /dev/dsk/c7t0d6
lvdisplay -v /dev/vg00/lvol4 |more
lvreduce -m 0 /dev/vg00/lvol4
lvdisplay -v /dev/vg00/lvol4 |more
pvmove -n /dev/vg00/lvol4 /dev/dsk/c0t6d0 /dev/dsk/c7t0d6

lvextend -L 1024 /dev/vg00/lvol3
fsadm -b 1024M /

pvmove -n /dev/vg00/lvol4 /dev/dsk/c7t0d6 /dev/dsk/c0t6d0
vgreduce /dev/vg00 /dev/dsk/c7t0d6

lvextend -m 1 /dev/vg00/lvol4


# bdf |grep vg00
/dev/vg00/lvol3 1048576 151640 890456 15% /
/dev/vg00/lvol1 125808 49064 64160 43% /stand
/dev/vg00/lvol7 4194304 2506048 1675672 60% /var
/dev/vg00/lvol6 3145728 1856304 1279456 59% /usr
/dev/vg00/lvol5 524288 160992 361104 31% /tmp
/dev/vg00/lvol4 2097152 1833552 261600 88% /opt
/dev/vg00/lvol8 1048576 622656 422632 60% /home
/dev/vg00/lvol10 2097152 1270980 774595 62% /app


Rgds...Geoff