Common Linux Commands daily work routine Linux commands

 

How to know CPU info

     cat /proc/cpuinfo

     arch

 

How to know memory info:

cat /proc/meminfo

or

sudo dmidecode -t memory

free

 

How to know Linux release info

CentOS:

vim /etc/redhat-release

 

How to check if Mysql running?

sudo netstat -tap | grep mysql

 

 

How to check if one pkg is installed?

     dpkg -l | grep mysql

 

 

 

 

How to check linux version

redhat: rpm -q redhat-release-server

 

How to check free disk space

     df -h

 

 

How to check size of folder

 [mashuai191@instance-1 ~]$ sudo du -h --max-depth=1 /home/

5.6G / home / mashuai191
4.1G / home / rsa-key-20190322mashuai191
9.6G / home /

Get the most CPU resources 10 processes under linux, you can use the following command combinations:

 

ps aux|head -1;ps aux|grep -v PID|sort -rn -k +3|head

 

 

 

To get the most memory resources 10 processes under linux, you can use the following command combinations:

 

ps aux|head -1;ps aux|grep -v PID|sort -rn -k +4|head

 

 

Network config:

Config hostname:

 

Redhat:

     hostname xxx

     Start to take effect, modify / etc / sysconfig / network

 

 

 

extract rpm into one directory

rpm2cpio logrotate-1.0-1.i386.rpm | cpio -ivd

 

 

Add date for created file

cp /etc/login.defs /etc/login.defs.`date +"%Y%m%d"`

 

 

 

vi copies of all

gg"+yG

 

 

man distortion output to a file, solution follows

man command | col -b >/home/command.txt

 

 

 

CentOS win7 shared access

     mount -t cifs -o sec=ntlm, password="" //10.200.78.2/f /home/mashuai/A_B_port/team_share_drive

 

 

user login history:

who /var/log/wtmp

last 

     -w full username/domain

 

 

Find hang process:

ps aux | grep -w 'D'

 

 

 

Redirect prints

1.    ]$ cmd 2>/dev/null, redirect stderr to null
2.  ]$ cmd 2>&1 1>/dev/null, Capturing STDERR only

 

 

 

 

CentOS

     package:

          yum install docker-ce

          yum list docker-ce.x86_64  --showduplicates

          yum remove docker-ce

 

 

     systemctl start docker

 

 

bash stint with the welcome message: / etc / issue, / etc / motd

 

Login bash to read the file

1. / Etc / profile: This is the overall system configuration, you should not modify this file; it will call / etc / inputrc, /etc/profile.d/*.sh, / etc / sysconfig / i18n
2. ~ / .Bash_profile or ~ / .bash_login or ~ / .profile: belongs to the user's personal configuration, you have to change your own data, is written here! In fact, the login shell bash configuration wherein a read only three documents above is sequentially read in the order above. Therein will call ~ / .bashrc

Non-Login bash to read the file

      ~/.bashrc

 

su command

su using non-login way to become root, or the previous user's environment variables

su - to become root login mode, switched to the environment variables of the root

 

 

 

netstat

     The computer network port detection

traceroute

     Multi-machine network detection