Which Release Version of Ubuntu Do You Have?
Knowing the exact release version allows you to perform upgrades properly and lets you know about known vulnerabilities. The Ubuntu Release Schedule states that 14.04 LTS will be supported until April 2019 but 14.10 will will only be supported until July 23, 2015. Make sure you build your servers with the LTS version so you can get updates for the longest possible period. Here are the commands that tell you what version of Ubuntu you are running, along with example output:
Ubuntu 14.10
user@somesite# uname -a
Linux somesite.com 3.16.0-28-generic #37-Ubuntu SMP Mon Dec 8 17:15:28 UTC 2014 x86_64 x86_64 x86_64 GNU/Linux
user@somesite# lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu 14.10
Release: 14.10
Codename: utopic
user@somesite# cat /etc/lsb-release
DISTRIB_ID=Ubuntu
DISTRIB_RELEASE=14.10
DISTRIB_CODENAME=utopic
DISTRIB_DESCRIPTION="Ubuntu 14.10"
Ubuntu 14.04 LTS
user@somesite# uname -a
Linux somesite.com 3.13.0-77-generic #121-Ubuntu SMP Wed Jan 20 10:50:42 UTC 2016 x86_64 x86_64 x86_64 GNU/Linux
user@somesite# lsb_release -a
lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu 14.04.3 LTS
Release: 14.04
Codename: trusty
user@somesite# cat /etc/lsb-release
DISTRIB_ID=Ubuntu
DISTRIB_RELEASE=14.04
DISTRIB_CODENAME=trusty
DISTRIB_DESCRIPTION="Ubuntu 14.04.3 LTS"