I just setup an EC2 instance running Linux. Is there a way to get the version/distribution of Linux that is running on the instance via the terminal?
The portable command for Linux Standard Base-compatible distributions (which is pretty much everything popular) is
lsb_release. The distribution can be obtained by "-i" and the version comes from "-r". The "-s" option suppresses the name column and just shows the value, and -a shows everything
lsb_release knows about the system. So, for example on a RHEL 5.5 system:
$ lsb_release -s -i RedHatEnterpriseServer $ lsb_release -s -r 5.5 $ lsb_release -a LSB Version: :core-3.1-amd64:core-3.1-ia32:core-3.1-noarch:graphics-3.1-amd64:graphics-3.1-ia32:graphics-3.1-noarch Distributor ID: RedHatEnterpriseServer Description: Red Hat Enterprise Linux Server release 5.5 (Tikanga) Release: 5.5 Codename: Tikanga
If you're on Red Hat, SuSE, Ubuntu, Debian, or anything else derived from those (Fedora, CentOS, whatever), this command will work. Otherwise, you'll have to figure out some distro-specific info. RedHat, for example again, installs a package named
redhat-release and creates a file in /etc:
$ rpm -q redhat-release redhat-release-5Server-220.127.116.11 $ cat /etc/redhat-release Red Hat Enterprise Linux Server release 5.5 (Tikanga)
Here's what it looks like on a freshly-provisioned (Feb 2, 2017) Amazon Linux 2 system - after I reset the hostname:
[ec2-user@fresh-amazon-host ~]$ cat /etc/system-release Amazon Linux release 2.0 (2017.12) LTS Release Candidate [ec2-user@fresh-amazon-host ~]$ cat /etc/os-release NAME="Amazon Linux" VERSION="2.0 (2017.12)" ID="amzn" ID_LIKE="centos rhel fedora" VERSION_ID="2.0" PRETTY_NAME="Amazon Linux 2.0 (2017.12) LTS Release Candidate" ANSI_COLOR="0;33" CPE_NAME="cpe:2.3:o:amazon:amazon_linux:2.0" HOME_URL="https://amazonlinux.com/"
IMHO, you really should use
lsb_release if it's available. If you're just doing it visually,
lsb_release -a is easy to remember and reasonably easy to read. But if that's not an option, /etc/os-release is populated as above on quite a few recent Linux OS versions.