. show linux version

$ uname -a
$ cat /proc/version
$ cat /proc/sys/kernel/{ostype,osrelease,version}
$ lsb_release -a
$ cat /etc/*release

. setterm (Disable PC speaker beep)

$ setterm -blength 0

. apt

# cd /etc/apt/
# wget http://mirrors.163.com/.help/sources.list.jessie -O sources.list
# apt-get update

. vim

# apt-get install vim

basic configuration

" line enables syntax highlighting
syntax on

" display line number
set number

" disable vim swap and backup
set nobackup
set nowritebackup
set noswapfile

" expands tab as spaces
set expandtab
set tabstop=4
set shiftwidth=4

" UTF-8
set encoding=utf-8
set fileencoding=utf-8
set fileencodings=ucs-bom,utf-8,chinese
set ambiwidth=double

. sudo

install

# apt-get install sudo

configuration

# usermod -aG sudo x # x is my login user name

. home directory for user [x]

# mkdir -p /home/x
# chown x:x /home/x
# usermod -d /home/x -m x

. OpenSSH

install

    # apt-get install openssh-server

start

    # /etc/init.d/ssh start

. gcc

# apt-get install gcc
# apt-get install make

. git

# apt-get install git

base_completion

# apt-get install git-core bash-completion

configuration

$ git config --global user.name "John Doe"
$ git config --global user.email johndoe@example.com

$ git config --global core.editor emacs

configuring a remote for a fork

$ git remote -v

$ git remote add upstream https://github.com/ORIGINAL_OWNER/ORIGINAL_REPOSITORY.git

syncing a fork

$ git fetch upstream
$ git checkout master
$ git merge upstream/master

. pip

install

# cp /tmp
# wget https://bootstrap.pypa.io/get-pip.py -O get-pip.py
# python get-pip.py

configuration

Per-user:

  • On Unix the default configuration file is: $HOME/.config/pip/pip.conf which respects the XDG_CONFIG_HOME environment variable.

  • On Mac OS X the configuration file is $HOME/Library/Application Support/pip/pip.conf.

  • On Windows the configuration file is %APPDATA%\pip\pip.ini.

There are also a legacy per-user configuration file which is also respected, these are located at:

  • On Unix and Mac OS X the configuration file is: $HOME/.pip/pip.conf

  • On Windows the configuration file is: %HOME%\pip\pip.ini

You can set a custom path location for this config file using the environment variable PIP_CONFIG_FILE.

# mkdir /etc/pip
# vi /etc/pip/pip.ini

[global]
timeout=60
index-url=https://pypi.mirrors.ustc.edu.cn/simple

# echo 'PIP_CONFIG_FILE="/etc/pip/pip.ini"' >> /etc/bash.bashrc

Inside a virtualenv:

  • On Unix and Mac OS X the file is $VIRTUAL_ENV/pip.conf

  • On Windows the file is: %VIRTUAL_ENV%\pip.ini

Site-wide:

  • On Unix the file may be located in /etc/pip.conf. Alternatively it may be in a “pip” subdirectory of any of the paths set in the environment variable XDG_CONFIG_DIRS (if it exists), for example /etc/xdg/pip/pip.conf.

  • On Mac OS X the file is: /Library/Application Support/pip/pip.conf

  • On Windows XP the file is: C:\Documents and Settings\All Users\Application Data\pip\pip.ini

  • On Windows 7 and later the file is hidden, but writeable at C:\ProgramData\pip\pip.ini

  • Site-wide configuration is not supported on Windows Vista

If multiple configuration files are found by pip then they are combined in the following order:

  • Firstly the site-wide file is read, then

  • The per-user file is read, and finally

  • The virtualenv-specific file is read.

. virtualenv

$ pip install virtualenv

. django

# pip install django

. uwsgi

# apt-get install python-dev
# pip install uwsgi

. nginx

# apt-get install nginx

. java

download

# wget --no-check-certificate --no-cookies --header "Cookie: oraclelicense=accept-securebackup-cookie"
\ http://download.oracle.com/otn-pub/java/jdk/8u66-b17/jdk-8u66-linux-x64.tar.gz
# tar xzf jdk-8u66-linux-x64.tar.gz
# mv jdk-8u66-linux-x64 /opt/java

configuration (/etc/profile or /etc/bash.bashrc)

JAVA_HOME=/opt/java # jdk1.8.0_66
JRE_HOME=$JAVA_HOME/jre
PATH=$PATH:$JAVA_HOME/bin:$JRE_HOME/bin
export JAVA_HOME
export JRE_HOME
export PATH

. Date & Time

  • Select a timezone

      # tzselect    # select timezone e.g. Asia/Shanghai
  # echo 'Asia/Shanghai' > /etc/timezone    # set timezone
  # ln -sf /usr/share/zoneinfo/Asia/Chongqing /etc/localtime

    OR

      # dpkg-reconfigure tzdata

  • Set the time manually

      date --set 1998-11-02
  date --set 21:08:00

  • Set the time automatically

    • Install ntp

        apt-get install ntp

    • Adjust /etc/ntp.conf

      Change the

        server pool.ntp.org

      line to

        server XX.pool.ntp.org

      where XX is your continent or two letter country code.

  • Force a clock update

      # service ntp stop
  # ntpd -gq
  # service ntp start

    OR

      # service ntp stop
  # ntpdate -s 3.cn.pool.ntp.org # synchronize date time.
  # service ntp start

  • Asia — asia.pool.ntp.org

    To use this pool zone, add the following to your ntp.conf file:

         server 0.asia.pool.ntp.org
     server 1.asia.pool.ntp.org
     server 2.asia.pool.ntp.org
     server 3.asia.pool.ntp.org

  • China — cn.pool.ntp.org

    There are not enough servers in this zone, so we recommend you use the Asia zone (asia.pool.ntp.org):

         server 0.asia.pool.ntp.org
     server 1.asia.pool.ntp.org
     server 2.asia.pool.ntp.org
     server 3.asia.pool.ntp.org

. Uninstall softeware / package

  • Uninstall / Delete / Remove Package

    • Remove package called mplaer,

        $ sudo apt-get remove mplayer

    • Remove package called lighttpd along with all configuration files,

        $ sudo apt-get --purge remove lighttpd

    • To list all installed package,

        $ dpkg --list

  • Uninstall files installed from a source code tar ball

    • Method # 1: make command

        # make uninstall

      This method sounds very easy but not supported by all tar balls make file.

    • Method # 2: find command

      First, make a list of all files on system before installing software i.e. pre-installation list of all files on your system,

        find /* > packagelist.b4

      Next compile and install the software (use configure & make to compile it),

        ./configure --option=1 --foo=bar etc
  make
  make install

      Now, make a list of all files on the system after installing software i.e. postinstall list,

        find /* > packagelist.after

      Finally compare both lists using the diff utility to find out what files are placed where.

        diff packagelist.b4 packagelist.after > package.uninstall.list

      Use the following small for loop at shell prompt to remove all files,

        for i in $(grep ">" package.uninstall.list | awk '{ print $2 }')
  do
   /bin/rm -fi "$i"
  done

. net-tools (CentOS)

  • ifconfig command not found

      # yum install net-tools

. Network Configuration (Debian)

The majority of network setup can be done via interfaces configuration file at /etc/network/interfaces.

  • Using DHCP to automatically configure the interface

      auto eth0
  allow-hotplug eth0
  iface eth0 inet dhcp

  • Configuring the interface manually

      auto eth0
  iface eth0 inet static
      address 192.0.2.7
      netmask 255.255.255.0
      gateway 192.0.2.254

  • Defining the (DNS) Nameservers

    The configuration file resolv.conf at /etc/resolv.conf contains information that allows a computer connected to a network to resolve names into addresses.

      nameserver 12.34.56.78
  nameserver 12.34.56.79

. redirecting to and from the standard file handles

Handle  Name    Description
0       stdin   Standard input
1       stdout  Standard output
2       stderr  Standard error

  • redirect stderr to stdout

    $ command-name 2>&1

OR

$ command-name &>

  • examples

    Write all output data to file list.

      $ find / -name .bashrc > list 2>&1
  $ find / -name .bashrc &> list

References