Checking what version of Ubuntu you are running is very easy. From my own experience, there are multiple ways to check the Ubuntu version. You can either check from graphical interface version, or from command line in the local terminal session or via SSH. The following result has been tested from the command line that was run from the command remotely over SSH.
1. Check ubuntu version using “cat /etc/issue” command :
ehowstuff@ubuntu14:~$ cat /etc/issue Ubuntu 14.04 LTS \n \l
2. Check Ubuntu version using “cat /etc/lsb-release” command :
ehowstuff@ubuntu14:~$ cat /etc/lsb-release DISTRIB_ID=Ubuntu DISTRIB_RELEASE=14.04 DISTRIB_CODENAME=trusty DISTRIB_DESCRIPTION="Ubuntu 14.04 LTS"
3. Check Ubuntu version using “lsb_release -a” command :
ehowstuff@ubuntu14:~$ lsb_release -a No LSB modules are available. Distributor ID: Ubuntu Description: Ubuntu 14.04 LTS Release: 14.04 Codename: trusty
or you can have more option to filter out the result :
ehowstuff@ubuntu14:~$ lsb_release -d Description: Ubuntu 14.04 LTS ehowstuff@ubuntu14:~$ lsb_release -c Codename: trusty ehowstuff@ubuntu14:~$ lsb_release -r Release: 14.04
Additionaly, you can check all the info regarding kernel version :
ehowstuff@ubuntu14:~$ uname -a Linux ubuntu14 3.13.0-24-generic #46-Ubuntu SMP Thu Apr 10 19:11:08 UTC 2014 x86_64 x86_64 x86_64 GNU/Linux
or
ehowstuff@ubuntu14:~$ cat /proc/version Linux version 3.13.0-24-generic (buildd@panlong) (gcc version 4.8.2 (Ubuntu 4.8.2-19ubuntu1) ) #46-Ubuntu SMP Thu Apr 10 19:11:08 UTC 2014