查看redhat的版本

第一種： 
[root@css /]# cat /etc/redhat-release 
Red Hat Enterprise Linux AS release 4 (Nahant Update 2) 
第二種： 
[root@css /]# cat /etc/issue 
Red Hat Enterprise Linux AS release 4 (Nahant Update 2) 
Kernel \r on an \m 

查看核心版本： 
[root@css /]# cat /proc/version 
Linux version 2.6.9-22.ELsmp ([email protected]) (gcc version 3.4.4 20050721 (Red Hat 3.4.4-2)) #1 SMP Mon Sep 19 18:32:14 EDT 2005