Last system installation time

UNIX for Advanced & Expert Users
1

Hi,
What is the best way to find the last installation time of an unix based systems?Please advise

Thanks
Nagarajan G

2

installation time of what ? Package, update, patch, or the OS, which is unknown at this time ?

3

I wanted to know the last os reinstalltion time.I would be happy to get answers to others as well

Thanks
Nagarajan G

4

That's why I asked what is the OS in question. If such option exists, it will depend on the OS. For example, I have recently installed Fedora 8, which has this file in the root folder - "install.log.syslog". If I cat the file, I can see that generic users / gropus have beed added :

. So, I know that I installed this fedora 8 on oct 15

5

Hi,
I am using Suse Linux,

uname -a
Linux sekac092 2.6.5-7.244-bigsmp #1 SMP Mon Dec 12 18:32:25 UTC 2005 i686 athlon i386 GNU/Linux

cat /etc/SuSE-release
SUSE LINUX Enterprise Server 9 (i586)
VERSION = 9
PATCHLEVEL = 3

Thanks
Nagarajan G

6

I have exact the same release, but it's way too customized. OK, you can try looking at the files : /var/adm/YaST/y2pm and /var/log/update-messages - these are the only ones I was able to find with unchanged time stamps.

7

This is why I like to do a:
date > /etc/installationdate
after I install. (I do this after whatever I consider to be the installation... this includes some other software and patches if done immediately after the os installation and prior to my baseline backup.)

There may still be a way. Do a "ls -lc" on a few files that were part of the OS installation. Stuff in /lib, the init and cron programs, stuff like that. Unless all of this stuff has been patched, the earliest date may give you a clue. Problems with this include the fact the sytsem clock may have been way off during the install. But for a re-installation, there is a good chance that the hardware was keeping reasonable time. Do not use mod time "ls -l" because many installation procedures will set the mod time to whatever is on the installation media.

8

Thanks for you inputs

Thanks,
Nagarajan G