查看linux版本：

1) 登录到服务器执行 lsb_release -a ,即可列出所有版本信息,例如:

[root@3.5.5Biz-46 ~]# [root@q1test01 ~]# lsb_release -a
LSB Version: :core-3.0-amd64:core-3.0-ia32:core-3.0-noarch:graphics-3.0-amd64:graphics-3.0-

ia32:graphics-3.0-noarch
Distributor ID: RedHatEnterpriseAS
Description: Red Hat Enterprise Linux AS release 4 (Nahant Update 2)
Release: 4
Codename: NahantUpdate2
注:这个命令适用于所有的linux，包括Redhat、SuSE、Debian等发行版。

2) 登录到linux执行cat /etc/issue,例如如下:

[root@q1test01 ~]# cat /etc/issue
Red Hat Enterprise Linux AS release 4 (Nahant Update 2)
Kernel \r on an \m

3) 登录到linux执行cat /etc/redhat-release ,例如如下:

[root@q1test01 ~]# cat /etc/redhat-release
Red Hat Enterprise Linux AS release 4 (Nahant Update 2)
注:这种方式下可以直接看到具体的版本号，比如 AS4 Update 1

4) 登录到linux执行rpm -q redhat-release ,例如如下:

[root@q1test01 ~]# rpm -q redhat-release
redhat-release-4AS-3
注:这种方式下可看到一个所谓的release号，比如上边的例子是3
这个release号和实际的版本之间存在一定的对应关系，如下：
redhat-release-3AS-1 -> Redhat Enterprise Linux AS 3
redhat-release-3AS-7.4 -> Redhat Enterprise Linux AS 3 Update 4
redhat-release-4AS-2 -> Redhat Enterprise Linux AS 4
redhat-release-4AS-2.4 -> Redhat Enterprise Linux AS 4 Update 1
redhat-release-4AS-3 -> Redhat Enterprise Linux AS 4 Update 2
redhat-release-4AS-4.1 -> Redhat Enterprise Linux AS 4 Update 3
redhat-release-4AS-5.5 -> Redhat Enterprise Linux AS 4 Update 4
另:第3)、4)两种方法只对Redhat Linux有效.