CentOS or RedHat Enterprise Linux is popular enterprise level Linux distribution. Different versions of the CentOS and RHEL is use In enterprise environment. Because of its stability and long time support old versions of CentOS and RHEL systems works in production too. In this tutorial w will look different ways to check and find CentOS and RHEL systems.
hostnamectl Command
hostnamectl
is very useful command which provides some basic information about the CentOS system like version. We can run command and see the Operating System:
line which is CentOS 7
$ hostnamectl

Rpm Command
rpm
is a tool used to manage system tools and packages. As packages are compiled according to operating system version and architecture rpm
command has information about the CentOS version and architecture too. We can use--query centos-release
option in order to list CentOS version like below.
$ rpm --query centos-release

lsb_release Command
lsb_release
command is mainly designed to provide the CentOS version and subversion. By default it is not installed but we can install it like below.
$ yum install redhat-lsb
and then we can run like below.
$ lsb_release -d

Release Files
Release versions of CentOS and RedHat also saved in different files according to the version of the system. Here list of the files those provides the system version.
- /etc/centos-release
- /etc/os-release
- /etc/redhat-release
- /etc/systemm-release
We can run a single cat
command which will print version information from all of them like below.
$ cat /etc/*release

As we can see we will get a lot of duplicate but consistent version information from this command.