centos查看系统版本
cat /etc/redhat-release
CentOS Linux release 7.2.1511 (Core) 
 
1)查看centos内核的版本：
[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)显示系统名、节点名称、操作系统的发行版号、操作系统版本、运行系统的机器 ID 号
[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)显示操作系统的发行版号
[root@localhost ~]#  uname -r
2.6.18-194.el5
 
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:
[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
 
 
​​centos查看系统cpu个数、核心​​​​数​​、线程数
1.查看物理cpu个数
grep 'physical id' /proc/cpuinfo | sort -u | wc -l    
   2
2.查看核心数量，即每个物理CPU中core的个数(即核数)
 grep 'core id' /proc/cpuinfo | sort -u | wc -l     6
3.查看线程数（逻辑CPU的个数）
grep 'processor' /proc/cpuinfo | sort -u | wc -l 
   24
4.查看cpu型号
dmidecode -s processor-version
5.查看内存方法
 grep MemTotal /proc/meminfo# 总核数 = 物理CPU个数 X 每颗物理CPU的核数 
# 总逻辑CPU数 = 物理CPU个数 X 每颗物理CPU的核数 X 超线程数 
# 查看物理CPU个数
cat /proc/cpuinfo| grep "physical id"| sort| uniq| wc -l2

# 查看每个物理CPU中core的个数(即核数)
cat /proc/cpuinfo| grep "cpu cores"| uniq6

# 查看逻辑CPU的个数
cat /proc/cpuinfo| grep "processor"| wc -l24