[CentOS] Apparently no swap configured

Tue Oct 28 04:35:17 UTC 2008
Ian Masters <ian at acces.co.jp>

Hello,

I'm in a slightly unusual situation and I'd really appreciate some advice.

I installed CentOS 5.2 on a server about a month ago.

Today I happened to check the 'free' command and noticed that the Swap
line reads as follows:

Swap:            0          0          0

I'm pretty certain that when I installed the OS and created a custom
partition table, that I defined a swap partition, but there is no swap
line in
/etc/fstab either.

However the output of 'lvm> lvdisplay' contains the following information
(amongst others):

  --- Logical volume ---
  LV Name                /dev/VolGroup00/swap
  VG Name                VolGroup00
  LV UUID                7uOBcj-tN16-uAbO-3nyy-3scZ-SAEA-7HKWPW
  LV Write Access        read/write
  LV Status              available
  # open                 0
  LV Size                1.94 GB
  Current LE             62
  Segments               1
  Allocation             inherit
  Read ahead sectors     auto
  - currently set to     256
  Block device           253:5

Also 'ls' confirms that logical volume exists:

[root at mail ~]# ls -l /dev/VolGroup00/swap
lrwxrwxrwx 1 root root 27 Sep 30 11:30 /dev/VolGroup00/swap ->
/dev/mapper/VolGroup00-swap

I'd like to know:
1. How can I check how this logical volume is formatted (and if it is
formatted)?
2. Is it possible to use this logical volume? If I add a line to
/etc/fstab, what are the chances of rendering my system unbootable?

The server is in use and presently doesn't have any memory problems, and
while it's not mission critical server I'd rather not mess it up with
any ill-thought out tinkering.

If anyone can give me some advice on this I'd be very grateful.

Thanks

Ian Masters