How to find when Operating system was installed in linux CentOS and Red Hat

This is a short video to know how you can find out on which date the linux was installed.
It is applicable to Red Hat based linux distro.

Step 1 : First find out the basesystem rpm.

rpm -qa|grep basesystem

Step 2: Now copy the complete basesystem version no. and hit the below given command .
The output will show many info. See the “Install Date” , this is the date when OS was installed.

rpm -qi 

Note: This is applicable when you have done fresh installation without using any image. For eg. the case is not applicable if you are checking in VPS (Virtual Private Server).

Below given is another method which is sure shot case to case

Another method for finding Install Date of Linux Operating system (CentOS and Red Hat)

Here the logic is Linux OS is installed in / root partition. So we will see when the partition was created which is equivalent to when Linux was installed.

We will use tune2fs command

Step 1: First do “df -Th” to get info where the / is mounted. In below given example / is mounted in /dev/sda5 (In your Linux OS it would vary)

linux@tuxworld:/tmp$ df -h
Filesystem      Size  Used Avail Use% Mounted on
/dev/sda5        28G   25G  1.6G  95% /
udev            2.0G  4.0K  2.0G   1% /dev
tmpfs           796M  980K  795M   1% /run
none            5.0M     0  5.0M   0% /run/lock
none            2.0G   12M  2.0G   1% /run/shm
none            100M   56K  100M   1% /run/user
cgroup          2.0G     0  2.0G   0% /sys/fs/cgroup
/dev/sda7       9.2G  8.9G     0 100% /partition7
/dev/sda8        46G   41G  3.1G  93% /partition8
/dev/sda9        74G   40G   31G  57% /partition9
linux@tuxworld:/tmp$ 

Step 2 : Use the command tune2fs.

tune2fs -l /dev/sda5

The below given is with grep command.

root@tuxworld:~# tune2fs -l /dev/sda5 |grep  'Filesystem created'
Filesystem created:       Sat Feb 18 22:47:25 2012
root@tuxworld:~#

Here “Sat Feb 18 22:47:25 2012” is OS installation date