Linux Commands

NOTICE:

x10Hosting does not suppport any third party software. This KB article is intended for reference use only. We do not support our VPSs beyond hardware. We will not offer help on these commands. To get help on these commands, use the help system included with your OS, by typing man command or command –help.

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A few commands to help out on the command line / SSH login

ls Displays everything in the current directory

 ls -a Displays all files, including hidden

 ls -l Displays all files, along with the size and timestamp

 tar -zxpf Uncompresses tar.gz files

 tar -xpf Uncompresses .tar files

 gunzip Uncompresses .gz files

 cp /path/to/old /path/to/new Copies a file to a new file

 mv /path/to/old /path/to/new Moves a file to a new file, or rename

 mkdir Creates a directory

 rmdir Deletes a directory

 rm Deletes a file

 rm -rf Deletes a directory

 cd /path/to/dir Moves to a directory

 cd .. Move up one directory

 cd ~ Moves to your home directory

 cd – Moves to the previous directory

 pwd Displays the present working directory (the one you’re in)

 pico Edits a file

 ftp Connect to a FTP server

 lynx View a webpage

 df Displays the hard drive stats

 quota Displays your quota

 uptime Displays the uptime of the server

 uname -a Displays the operating system stats

 whoami Displays your info

 who Displays others connected to the server

 last Displays the last login

 whereis Tells where a file is located

 BitchX IRC Client

 mail Check your email

 ps -x Displays processes your running

 ps -a Displays all processes running

 ps -ux Displays running processes, with CPU/Memory usage

 kill pid#  Kills a process

 kill -9 pid# Kills an eggdrop process

 killall proc_name Kills all running process of the same type

 whatis Description of commands

 man command Displays help on the command (manual)

 nano Same as Pico (Use yum install nano if it doesn’t first work)

 Top – gives an overall view of what is going on with the server including memory usage, serve load and running processes “q” to exit top

 sar -q gives a report of the process list, 1 minute and 5 minute average load every 10 minutes since midnight server time

 tar -zcf filename.tar.gz file Tars up the file or directory of your choice, replace filename.tar.gz with the name you want your tar file to have…with the tar.gz extension on the end and replace file with the file or directory you want to tar up. Can also use a path/to/file for both.

 updatedb – Updates the locate/search DB.

netstat -n -p

 Useful to see who is connected to your server, this also resolves hostnames to IP addresses and the -p switch shows you what each person connected is doing and provides a PID for it if there is one… useful if you need to kill something

find / -user username

 Replace username with a username of one of your account to find all the files that belong to them. Also useful to add the |more switch so you can scroll one screen at a time. Ever have a client who seems to show a lot more files than are actually in their home directory? This is how you find those files and fix them. Common problem is cpmove files that don’t get properly deleted and get added to a users account.

/scripts/pkgacct2 username

 Replace username with a user on your system. This should be done from the home directory. Useful for manually backing up an account if whm copy account doesn’t work. Then just move (mv) the file to a home directory accessible via the web and

 chown user.user filename

 and chmod to 750 or 755 and you can wget it from a different server if need be.

/scripts/restorepkg username

 Once you’ve got the file and need to unpack it you use this command. The file should be in the /home directory to use this though. Remember folks…. username…. not cpmove-username.tar.gz

crontab -e

 edit the crontab file and see what is set to run in there.

–help (add to end of the command following a single space)

 Such as tar –help, similar to man it digs up info on any given command.

tail -10 filename

 gives you the last 10 lines of a file. Can change the # to whatever you want.

cp -R FileOrDirectory path/to/destination

 the -R allows you to copy an entire directory to somewhere else.

kill -9

 not just for eggdrops… it’s called a “hard kill” and handy for killing off any stubborn process that refuses to die.

whereis filename (use the * as a wildcard or for broader search)

 can also use locate or find (although locate is faster)

killall

 not just for killing programs.. you can also killall to kill all processes being run by a user. Handy if you have an abuser eating up system resources.

RESTART SERVICES:

service servicename restart

Stop a service:

 service servicename stop

Start a service:

 service servicename start

Status (doesn’t work on all):

 service servicename status

On a RedHat CPanel server, here are the useful services: (CentOS, x10’s default OS for VPSs, is a stripped-down RedHat OS.)

 bandmin

 chkservd

 cpanel

 crond

 exim

 httpd

 mysql

 named

 proftpd

CRON INFO:

 Root crontab: (can be used by any user with crontab permissions to edit their crontab. If you are running this as “root” it will edit root’s crontab, and the same goes for any other user. When “bob” runs crontab -e, he will edit his own crontab and not root’s, though he can only edit his own crontab if he has permissions.)

crontab -e

To edit a users cron jobs: (run as a super-user, such as root. not available to regular users.)

crontab -u username -e

Replace username with the actual username of the client you want to edit.

(We’re still talking about RedHat [CentOS] that is running cPanel below. You can do most, if not all, of this from the WHM, so feel free to skip ahead a bit. :P)

 /scripts/adddns Add a Dns Entry

 /scripts/addfpmail Install Frontpage Mail Exts

 /scripts/addservlets Add JavaServlets to an account (jsp plugin required)

 /scripts/adduser Add a User

 /scripts/admin Run WHM Lite

 /scripts/apachelimits Add Rlimits (cpu and mem limits) to apache.

 /scripts/dnstransfer Resync with a master DNS Server

 /scripts/editquota Edit A User’s Quota

 /scripts/finddev Search For Trojans in /dev

 /scripts/findtrojans Locate Trojan Horses

Suggested Usage:

/scripts/findtrojans < /var/log/trojans

 /scripts/fixtrojans < /var/log/trojans

 /scripts/fixcartwithsuexec Make Interchange work with suexec

 /scripts/fixinterchange Fix Most Problems with Interchange

 /scripts/fixtrojans Run on a trojans horse file created by findtrojans to remove them

 /scripts/fixwebalizer Run this if a user’s stats stop working

 /scripts/fixvaliases Fix a broken valias file

 /scripts/hdparamify Turn on DMA and 32bit IDE hard drive access (once per boot)

 /scripts/initquotas Re-scan quotas. Usually fixes Disk space display problems

 /scripts/initsuexec Turn on SUEXEC (probably a bad idea)

 /scripts/installzendopt Fetch + Install Zend Optimizer

 /scripts/ipusage Display Ipusage Report

 /scripts/killacct Terminate an Account

 /scripts/killbadrpms Delete \”Security Problem Infested RPMS\”

 /scripts/mailperm Fix Various Mail Permission Problems

 /scripts/mailtroubleshoot Attempt to Troubleshoot a Mail Problem

 /scripts/mysqlpasswd Change a Mysql Password

 /scripts/quicksecure Kill Potential Security Problem Services

 /scripts/rebuildippool Rebuild Ip Address Pool

 /scripts/remdefssl Delete Nasty SSL entry in apache default httpd.conf

 /scripts/restartsrv Restart a Service (valid services: httpd,proftpd,exim,sshd,cppop,bind,mysql)

 /scripts/rpmup Syncup Security Updates from RedHat/Mandrake

 /scripts/runlogsnow Force a webalizer/analog update.

 /scripts/secureit Remove non-important suid binaries

 /scripts/setupfp4 Install Frontpage 4+ on an account.

 /scripts/simpleps Return a Simple process list. Useful for finding where cgi scripts are running from.

 /scripts/suspendacct Suspend an account

 /scripts/sysup Syncup Cpanel RPM Updates

 /scripts/ulimitnamed RH 6 only. Install a version of bind to handle many many zones.

 /scripts/unblockip Unblock an IP

 /scripts/unsuspendacct UnSuspend an account

 /scripts/upcp Update Cpanel

 /scripts/updatenow Update /scripts

 /scripts/wwwacct Create a New Account

Delete MRTG

 rpm -e –nodeps `rpm -qa|grep mrtg`

Empty /tmp folder

 rm -R -f /tmp/c*

 rm -R -f /tmp/s*

 rm -R -f /tmp/p*

 rm -R -f /tmp/*_*

 rm -R -f /tmp/*-*