CentOS查看版本号，最合适的命令为：

cat /etc/redhat-release

以下为测试过程：

1.      cat /etc/redhat-release

[root@localhost ~]# cat /etc/redhat-release

CentOS Linux release 7.2.1511 (Core)

 

2.      lsb_release

命令没找到

 

3.      uname -a

[root@localhost ~]# uname -a

Linux localhost.localdomain3.10.0-327.el7.x86_64 #1 SMP Thu Nov 19 22:10:57 UTC 2015 x86_64 x86_64 x86_64GNU/Linux

 

4.      cat /proc/version

[root@localhost ~]# cat /proc/version

Linux version 3.10.0-327.el7.x86_64(builder@kbuilder.dev.centos.org) (gcc version 4.8.3 20140911 (Red Hat 4.8.3-9)(GCC) ) #1 SMP Thu Nov 19 22:10:57 UTC 2015

参考：

如何查看已安装的CentOS版本信息：

1)[root@localhost ~]# cat /proc/version

Linux version 2.6.18-194.el5 (mockbuild@builder10.centos.org) (gcc version 4.1.2 20080704 (Red Hat 4.1.2-48)) #1 SMP Fri Apr 2 14:58:14 EDT 2010

2)

[root@localhost ~]# uname -a

Linux localhost.localdomain 2.6.18-194.el5 #1 SMP Fri Apr 2 14:58:14 EDT 2010 x86_64 x86_64 x86_64 GNU/Linux

3)

[root@localhost ~]# uname -r

2.6.18-194.el5

2. 查看linux版本：

1) 列出所有版本信息,

[root@localhost ~]# 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: CentOS

Description:    CentOS release 5.5 (Final)

Release:        5.5

Codename:      Final

注:这个命令适用于所有的linux，包括RedHat、SUSE、Debian等发行版。

2) 执行cat /etc/issue,例如如下:

[root@localhost ~]# cat /etc/issue

CentOS release 5.5 (Final)

Kernel r on an m

3) 执行cat /etc/redhat-release ,例如如下:

[root@localhost ~]# cat /etc/redhat-release

CentOS release 5.5 (Final)

查看系统是64位还是32位:

1、getconf LONG_BIT or getconf WORD_BIT

[root@localhost ~]# getconf LONG_BIT

64

2、file /bin/ls

[root@localhost ~]# file /bin/ls

/bin/ls: ELF 64-bit LSB executable, AMD x86-64, version 1 (SYSV), for GNU/Linux 2.6.9, dynamically linked (uses shared libs), for GNU/Linux 2.6.9, stripped

3、lsb_release  -a

[root@localhost ~]# 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: CentOS

Description:    CentOS release 5.5 (Final)

Release:        5.5

Codename:      Final

4、或者是使用查看文件的方法。

vim /ect/issue