View Linux kernel version and system version information

First, see Linux kernel version command (2 methods)
1,

2, uname -a

Second, view the version of Linux system command (3 methods)
1, lsb_release -a

after the test found that the command applies to Centos, Ubuntu. Without this command in redhat.

2, cat / etc / redhat-release, this method is only suitable system Linux Redhat

3, cat / etc / issue, Centos, Redhat General