Alias adalah sebuah sintak yang dapat dibuat untuk menyingkat perintah pada Bash Shell. Alias membolehkan pengguna untuk menjalankan beberapa perintah atau grup dari suatu perintah dengan cara mengganti perintah tersebut menjadi lebih sederhana.
Task: List Alias
$ alias
Contoh hasil yang muncul.
alias ..='cd ..'
alias alert='notify-send --urgency=low -i "$([ $? = 0 ] && echo terminal || echo error)" "$(history|tail -n1|sed -e '\''s/^\s*[0-9]\+\s*//;s/[;&|]\s*alert$//'\'')"'
alias egrep='egrep --color=auto'
alias fgrep='fgrep --color=auto'
alias grep='grep --color=auto'
Task: mendefinisikan / membuat alias
Untuk membuat alias bisa menggunakan sintak berikut:
$ alias name=value
$ alias name='command'
$ alias name='command arg1 arg2'
$ alias name='path/to/script'
$ alias name='path/to/script.sh arg1'
Contoh sederhana menggunakan alias untuk membersihkan layar terminal.
$ alias c='clear'
Dengan mengetik 'c' lalu enter maka layar terminal anda akan bersih.
Task: men-disable sebuah secara sementara
Sebuah alias dapat didisable secara sementara menggunakan perintah berikut:
## path/to/full/command
$ /usr/bin/clear
## call alias with a backslash ##
$ \c
Task: menghapus alias yang sudah dibuat sebelumnya
Anda dapat menggunakan unalias untuk menghapus alias yang sudah dibuat
$ unalias aliasname
Dalam contoh ini kita akan menghapus alias 'c' yang sudah dibuat tadi, seperti berikut:
$ unalias c
Anda dapat juga menghapus alias melalui file
~/.bashrc melalui text editor (akan dibahas selanjutnya)
Task: membuat alias secara permanen
Pada dasarnya Alias yang kita buat tadi hanya bisa digunakan dalam satu session saja, artinya setiap kita me-restart komputer Alias tersebut akan hilang. Untuk menghindari masalah itu, kita bisa menambahkan Alias pada file ~/.bashrc , seperti berikut:
$ sudo gedit ~/.bashrc
Seperti contoh Alias 'c' sebelumnya dapat dibuat permanent dengan menambahkan sintak berikut,
alias c='clear'
Simpan dan close file, coba restart atau log out maka alias 'c' akan tetap ada.
Contoh tambahan:
# jika user bukan root, maka jalankan perintah dengan menambahkan sudo #
if [$UID -ne 0]; then
alias reboot = 'sudo reboot'
alias update = 'sudo apt-get update'
fi
30 Cara menggunakan Alias dengan baik
Nama alias dapat anda sesuikan dengan kebutuhan, tergantung cara anda menggunakan:
#1: Control ls command output
Perintah ls adalah untuk menampilkan isi dari suatu direktori.
## Colorize the ls output ##
alias ls='ls --color=auto'
## Use a long listing format ##
alias ll='ls -la'
## Show hidden files ##
alias l.='ls -d .* --color=auto'
|
#2: Control cd command behavior
## get rid of command not found ##
alias cd..='cd ..'
## a quick way to get out of current directory ##
alias ..='cd ..'
alias ...='cd ../../../'
alias ....='cd ../../../../'
alias .....='cd ../../../../'
alias .4='cd ../../../../'
alias .5='cd ../../../../..'
|
#3: Control grep command output
## Colorize the grep command output for ease of use (good for log files)##
alias grep='grep --color=auto'
alias egrep='egrep --color=auto'
alias fgrep='fgrep --color=auto'
|
#4: Start calculator with math support
#4: Generate sha1 digest
alias sha1='openssl sha1'
|
#5: Create parent directories on demand
#6: Colorize diff output
# install colordiff package :)
alias diff='colordiff'
|
#7: Make mount command output pretty and human readable format
alias mount='mount |column -t'
|
#8: Command short cuts to save time
# handy short cuts #
alias h='history'
alias j='jobs -l'
|
#9: Create a new set of commands
alias path='echo -e ${PATH//:/\\n}'
alias now='date +"%T"'
alias nowtime=now
alias nowdate='date +"%d-%m-%Y"'
|
#10: Set vim as default
alias vi=vim
alias svi='sudo vi'
alias vis='vim "+set si"'
alias edit='vim'
|
#11: Control output of networking tool called ping
# Stop after sending count ECHO_REQUEST packets #
alias ping='ping -c 5'
# Do not wait interval 1 second, go fast #
alias fastping='ping -c 100 -s.2'
|
#12: Show open ports
alias ports='netstat -tulanp'
|
#13: Wakeup sleeping servers
## replace mac with your actual server mac address #
alias wakeupnas01='/usr/bin/wakeonlan 00:11:32:11:15:FC'
alias wakeupnas02='/usr/bin/wakeonlan 00:11:32:11:15:FD'
alias wakeupnas03='/usr/bin/wakeonlan 00:11:32:11:15:FE'
|
#14: Control firewall (iptables) output
## shortcut for iptables and pass it via sudo#
alias ipt='sudo /sbin/iptables'
# display all rules #
alias iptlist='sudo /sbin/iptables -L -n -v --line-numbers'
alias iptlistin='sudo /sbin/iptables -L INPUT -n -v --line-numbers'
alias iptlistout='sudo /sbin/iptables -L OUTPUT -n -v --line-numbers'
alias iptlistfw='sudo /sbin/iptables -L FORWARD -n -v --line-numbers'
alias firewall=iptlist
|
#15: Debug web server / cdn problems with curl
# get web server headers #
alias header='curl -I'
# find out if remote server supports gzip / mod_deflate or not #
alias headerc='curl -I --compress'
|
#16: Add safety nets
# do not delete / or prompt if deleting more than 3 files at a time #
alias rm='rm -I --preserve-root'
# confirmation #
alias mv='mv -i'
alias cp='cp -i'
alias ln='ln -i'
# Parenting changing perms on / #
alias chown='chown --preserve-root'
alias chmod='chmod --preserve-root'
alias chgrp='chgrp --preserve-root'
|
#17: Update Debian Linux server
# distro specific - Debian / Ubuntu and friends #
# install with apt-get
alias apt-get="sudo apt-get"
alias updatey="sudo apt-get --yes"
# update on one command
alias update='sudo apt-get update && sudo apt-get upgrade'
|
#18: Update RHEL / CentOS / Fedora Linux server
yum command is a package management tool for RHEL / CentOS / Fedora Linux and friends:
## distrp specifc RHEL/CentOS ##
alias update='yum update'
alias updatey='yum -y update'
|
#19: Tune sudo and su
# become root #
alias root='sudo -i'
alias su='sudo -i'
|
#20: Pass halt/reboot via sudo
# reboot / halt / poweroff
alias reboot='sudo /sbin/reboot'
alias poweroff='sudo /sbin/poweroff'
alias halt='sudo /sbin/halt'
alias shutdown='sudo /sbin/shutdown'
|
#21: Control web servers
# also pass it via sudo so whoever is admin can reload it without calling you #
alias nginxreload='sudo /usr/local/nginx/sbin/nginx -s reload'
alias nginxtest='sudo /usr/local/nginx/sbin/nginx -t'
alias lightyload='sudo /etc/init.d/lighttpd reload'
alias lightytest='sudo /usr/sbin/lighttpd -f /etc/lighttpd/lighttpd.conf -t'
alias httpdreload='sudo /usr/sbin/apachectl -k graceful'
alias httpdtest='sudo /usr/sbin/apachectl -t && /usr/sbin/apachectl -t -D DUMP_VHOSTS'
|
#22: Alias into our backup stuff
# if cron fails or if you want backup on demand just run these commands #
# again pass it via sudo so whoever is in admin group can start the job #
# Backup scripts #
alias backup='sudo /home/scripts/admin/scripts/backup/wrapper.backup.sh --type local --taget /raid1/backups'
alias nasbackup='sudo /home/scripts/admin/scripts/backup/wrapper.backup.sh --type nas --target nas01'
alias s3backup='sudo /home/scripts/admin/scripts/backup/wrapper.backup.sh --type nas --target nas01 --auth /home/scripts/admin/.authdata/amazon.keys'
alias rsnapshothourly='sudo /home/scripts/admin/scripts/backup/wrapper.rsnapshot.sh --type remote --target nas03 --auth /home/scripts/admin/.authdata/ssh.keys --config /home/scripts/admin/scripts/backup/config/adsl.conf'
alias rsnapshotdaily='sudo /home/scripts/admin/scripts/backup/wrapper.rsnapshot.sh --type remote --target nas03 --auth /home/scripts/admin/.authdata/ssh.keys --config /home/scripts/admin/scripts/backup/config/adsl.conf'
alias rsnapshotweekly='sudo /home/scripts/admin/scripts/backup/wrapper.rsnapshot.sh --type remote --target nas03 --auth /home/scripts/admin/.authdata/ssh.keys --config /home/scripts/admin/scripts/backup/config/adsl.conf'
alias rsnapshotmonthly='sudo /home/scripts/admin/scripts/backup/wrapper.rsnapshot.sh --type remote --target nas03 --auth /home/scripts/admin/.authdata/ssh.keys --config /home/scripts/admin/scripts/backup/config/adsl.conf'
alias amazonbackup=s3backup
|
#23: Desktop specific – play avi/mp3 files on demand
## play video files in a current directory ##
# cd ~/Download/movie-name
# playavi or vlc
alias playavi='mplayer *.avi'
alias vlc='vlc *.avi'
# play all music files from the current directory #
alias playwave='for i in *.wav; do mplayer "$i"; done'
alias playogg='for i in *.ogg; do mplayer "$i"; done'
alias playmp3='for i in *.mp3; do mplayer "$i"; done'
# play files from nas devices #
alias nplaywave='for i in /nas/multimedia/wave/*.wav; do mplayer "$i"; done'
alias nplayogg='for i in /nas/multimedia/ogg/*.ogg; do mplayer "$i"; done'
alias nplaymp3='for i in /nas/multimedia/mp3/*.mp3; do mplayer "$i"; done'
# shuffle mp3/ogg etc by default #
alias music='mplayer --shuffle *'
|
#24: Set default interfaces for sys admin related commands
## All of our servers eth1 is connected to the Internets via vlan / router etc ##
alias dnstop='dnstop -l 5 eth1'
alias vnstat='vnstat -i eth1'
alias iftop='iftop -i eth1'
alias tcpdump='tcpdump -i eth1'
alias ethtool='ethtool eth1'
# work on wlan0 by default #
# Only useful for laptop as all servers are without wireless interface
alias iwconfig='iwconfig wlan0'
|
#25: Get system memory, cpu usage, and gpu memory info quickly
## pass options to free ##
alias meminfo='free -m -l -t'
## get top process eating memory
alias psmem='ps auxf | sort -nr -k 4'
alias psmem10='ps auxf | sort -nr -k 4 | head -10'
## get top process eating cpu ##
alias pscpu='ps auxf | sort -nr -k 3'
alias pscpu10='ps auxf | sort -nr -k 3 | head -10'
## Get server cpu info ##
alias cpuinfo='lscpu'
## older system use /proc/cpuinfo ##
##alias cpuinfo='less /proc/cpuinfo' ##
## get GPU ram on desktop / laptop##
alias gpumeminfo='grep -i --color memory /var/log/Xorg.0.log'
|
#26: Control Home Router
# Reboot my home Linksys WAG160N / WAG54 / WAG320 / WAG120N Router / Gateway from *nix.
alias rebootlinksys="curl -u 'admin:my-super-password' 'http://192.168.1.2/setup.cgi?todo=reboot'"
# Reboot tomato based Asus NT16 wireless bridge
alias reboottomato="ssh admin@192.168.1.1 /sbin/reboot"
|
#27 Resume wget by default
## this one saved by butt so many times ##
alias wget='wget -c'
|
#28 Use different browser for testing website
## this one saved by butt so many times ##
alias ff4='/opt/firefox4/firefox'
alias ff13='/opt/firefox13/firefox'
alias chrome='/opt/google/chrome/chrome'
alias opera='/opt/opera/opera'
#default ff
alias ff=ff13
#my default browser
alias browser=chrome
|
#29: A note about ssh alias
Do not create ssh alias, instead use ~/.ssh/config OpenSSH SSH client configuration files. It offers more option. An example:
Host server10
Hostname 1.2.3.4
IdentityFile ~/backups/.ssh/id_dsa
user foobar
Port 30000
ForwardX11Trusted yes
TCPKeepAlive yes
|
You can now connect to peer1 using the following syntax:
$ ssh server10
#30: It’s your turn to share…
## set some other defaults ##
alias df='df -H'
alias du='du -ch'
# top is atop, just like vi is vim
alias top='atop'
## nfsrestart - must be root ##
## refresh nfs mount / cache etc for Apache ##
alias nfsrestart='sync && sleep 2 && /etc/init.d/httpd stop && umount netapp2:/exports/http && sleep 2 && mount -o rw,sync,rsize=32768,wsize=32768,intr,hard,proto=tcp,fsc natapp2:/exports /http/var/www/html && /etc/init.d/httpd start'
## Memcached server status ##
alias mcdstats='/usr/bin/memcached-tool 10.10.27.11:11211 stats'
alias mcdshow='/usr/bin/memcached-tool 10.10.27.11:11211 display'
## quickly flush out memcached server ##
alias flushmcd='echo "flush_all" | nc 10.10.27.11 11211'
## Remove assets quickly from Akamai / Amazon cdn ##
alias cdndel='/home/scripts/admin/cdn/purge_cdn_cache --profile akamai'
alias amzcdndel='/home/scripts/admin/cdn/purge_cdn_cache --profile amazon'
## supply list of urls via file or stdin
alias cdnmdel='/home/scripts/admin/cdn/purge_cdn_cache --profile akamai --stdin'
alias amzcdnmdel='/home/scripts/admin/cdn/purge_cdn_cache --profile amazon --stdin'
|
Selamat mencoba...
Leave a Comment