Essential Cluster OS Commands

Essential cluster Os Commands class 3

Essential Cluster OS Commands Class 3

SSH ssh (SSH client) is a program for logging into a remote machine and for executing commands on a remote machine. It is intended to replace rlogin and rsh, and provide secure encrypted communications between two untrusted hosts over an insecure network Usage ssh [-l login name]hostname user @hostname [command] EXample ssh-l peter tdgrocks sci hkbu. edu. hk ssh peter@tdgrocks sci hkbu. edu. hk

SSH • ssh (SSH client) is a program for logging into a remote machine and for executing commands on a remote machine. It is intended to replace rlogin and rsh, and provide secure encrypted communications between two untrusted hosts over an insecure network. • Usage: – ssh [-l login_name] hostname | user@hostname [command] • Example: ssh -l peter tdgrocks.sci.hkbu.edu.hk ssh peter@tdgrocks.sci.hkbu.edu.hk

Common Linux Command Getting Help man [command]-manual pages apropos [keyword-Searches the manual pages for the keyord Directory Movement pwd -current directory path cd-change directory

Common Linux Command • Getting Help – man [command] - manual pages – apropos [keyword] - Searches the manual pages for the keyword • Directory Movement – pwd - current directory path – cd - change directory

Common Linux Command File/Directory Viewing -Is- list cat -display entire file more-page through file less-page forward and backward through file head- view first ten lines of file tail -view last ten lines of file

Common Linux Command • File/Directory Viewing – ls - list – cat - display entire file – more - page through file – less - page forward and backward through file – head - view first ten lines of file – tail - view last ten lines of file

Common Linux Command File/Directory Control cp-copy mv-move/rename rm- remove mkdir-make directory rmdir-remove directory In-create pseudonym(ink) chmod -change permissions touch -update access time (or create blank file

Common Linux Command • File/Directory Control – cp - copy – mv - move/rename – rm - remove – mkdir - make directory – rmdir - remove directory – ln - create pseudonym (link) – chmod - change permissions – touch - update access time (or create blank file)

Common Linux Command Searching locate- list files in filename database find -recursive file search grep-search file (also see"egrep"& fgrep") · Text editors vim- text editor pico-another text editor emacs -another text editor nano-and another text editor

Common Linux Command • Searching – locate - list files in filename database – find - recursive file search – grep - search file (also see "egrep" & "fgrep") • Text Editors – vim – text editor – pico - another text editor – emacs - another text editor – nano - and another text editor

Common Linux Command Compression tar-tape archiver gzip-GNu compression utility bzip2 -compression and package utility unzip uncompress zip files · Session and terminal history-command history clear - clear screen

Common Linux Command • Compression – tar - tape archiver – gzip - GNU compression utility – bzip2 - compression and package utility – unzip - uncompress zip files • Session and Terminal – history - command history – clear - clear screen

Common Linux Command User Information yppasswd -change user password (not available in our cluster) finger-display user() data, includes full name Who - display user(s) data W-display user(s)current activity System Usage ps -show processes kill -kill process uptime-system usage uptime

Common Linux Command • User Information – yppasswd - change user password (not available in our cluster) – finger - display user(s) data, includes full name – who - display user(s) data – w - display user(s) current activity • System Usage – ps - show processes – kill - kill process – uptime - system usage & uptime

Common Linux Command Misc ftp- simple File Transfer Protocol client sftp- Secure File Transfer Protocol client ssh- Secure shell ispell -interactively check spelling against system dictionary date-display date and time cal -display calendar wget-web content retriever(mirror)

Common Linux Command • Misc. – ftp - simple File Transfer Protocol client – sftp - Secure File Transfer Protocol client – ssh - Secure Shell – ispell - interactively check spelling against system dictionary – date - display date and time – cal - display calendar – wget - web content retriever (mirror)

Cluster-fork Rocks provides a simple tool for this purpose called cluster-fork. For example, to list all your processes on the compute nodes of the cluster cluster-fork ps -USUSER Cluster-fork is smart enough to ignore dead nodes. Usually the job is"blocking": cluster-fork waits for the job to start on one node before moving to the next

Cluster-fork • Rocks provides a simple tool for this purpose called cluster-fork. For example, to list all your processes on the compute nodes of the cluster: cluster-fork ps -U$USER • Cluster-fork is smart enough to ignore dead nodes. Usually the job is "blocking": cluster-fork waits for the job to start on one node before moving to the next