查看centos内核的版本

查看centos内核的版本：
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

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

root@localhost # uname -r
2.6.18-194.el5

1. 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