Common CentOS Commands

One: View CPU

More/proc/cpuinfo | grep "model name"
grep "model name"/proc/cpuinfo

If you feel the need to see more comfortable

grep "model Name"/proc/cpuinfo | Cut-f2-d:

Two: View memory

grep memtotal/proc/meminfo

grep Memtotal/proc/meminfo | Cut-f2-d:

Free-m |grep "Mem" | awk ' {print $} '

Three: Check whether the CPU is 32-bit or 64-bit

View the number of CPU bits (+ or 64)

Getconf Long_bit

Four: View the current version of Linux

More/etc/redhat-release
Cat/etc/redhat-release

V: View kernel version

Uname-r

Uname-a

VI: View current time

Date

The above has been described how to synchronize time,

Seven: View hard disks and partitions

Df-h

Fdisk-l

You can also view partitions

Du-sh

You can see all the space occupied

Du/etc-sh

You can see the size of this directory

Eight: View the installed packages

To view the packages installed on the system

Cat-n/root/install.log

More/root/install.log | Wc-l

See which packages are now installed

Rpm-qa

Rpm-qa | Wc-l

Yum List Installed | Wc-l

But strangely enough, the number of installation packages I've queried through RPM, and Yum, is not the same. No reason was found.

Nine: View the keyboard layout

Cat/etc/sysconfig/keyboard

Cat/etc/sysconfig/keyboard | grep KEYTABLE | Cut-f2-d=

Ten: View selinux status

Sestatus

Sestatus | Cut-f2-d:

Cat/etc/sysconfig/selinux

11: View Ip,mac Address

In the Ifcfg-eth0 file you can see Mac, Gateway and other information.

Ifconfig

Cat/etc/sysconfig/network-scripts/ifcfg-eth0 | grep ipaddr

Cat/etc/sysconfig/network-scripts/ifcfg-eth0 | grep ipaddr | Cut-f2-d=

Ifconfig eth0 |grep "inet addr:" |awk ' {print $} ' |cut-c 6-

Ifconfig | grep ' inet addr: ' | Grep-v ' 127.0.0.1′| Cut-d:-f2 | awk ' {print '} '

View Gateway

Cat/etc/sysconfig/network

View DNS

Cat/etc/resolv.conf

12: View Default language

Echo $LANG $LANGUAGE

cat/etc/sysconfig/i18n

13: View your time zone and whether to use UTC time

Cat/etc/sysconfig/clock

14: View Host Name

Hostname

Cat/etc/sysconfig/network

Modify the hostname is to modify this file, but also preferably the host file also modified.

# du-sh # View the size of the specified directory

# uptime # View System uptime, number of users, load

# cat/proc/loadavg # View System load

# iptables-l # View firewall settings
# route-n # View the routing table
# netstat-lntp # View all listening ports
# NETSTAT-ANTP # View all established connections
# netstat-s # View Network statistics

# w # View active Users
# ID # view specified user information
# last # View user log in log
# cut-d:-f1/etc/passwd # View All users of the system
# cut-d:-f1/etc/group # View all system groups
# crontab-l # View Current user's scheduled tasks
# chkconfig–list # List all system services
# Chkconfig–list | grep on # Lists all startup system services

Common CentOS Commands