Linux Commands Cheatsheet

15 May 2018

Commands chaining in terminal:

A; B    # Run A and then B, regardless of success of A
A && B  # Run B if and only if A succeeded
A || B  # Run B if and only if A failed
A &     # Run A in background.
Command Description
find / -name pg_hba.conf Find file ‘ph_hba.conf’ file starting from the root
grep -rnw '/path/to/somewhere/' -e 'pattern' -r is recursive
-n is line number
-w stands for match the whole word
-e is the pattern used during the search
grep -rni "string" * search some string recursively in all files where
-r = recursive i.e, search subdirectories within the current directory
-n = to print the line numbers to stdout
-i = case insensitive search
   
chkconfig --list List all services
service --status-all List running service
service postgresql96 status Check status of postgresql96 service
sudo service postgresql96 restart Restart postgresql96 service
   
du -hs * display summarized sized for each file and folder in current directory
h - human readable
s - summarized
   
yum list show all available packages
yum list installed show all installed packages
yum remove <package> remove selected package
rpm -qa list intalled packages
rpm -ivh <package> install selected package
rpm -e <package> remove selected package
apt list --installed list installed packages
   
ln -sfn <full-path> <link-name> create or update symbolic link
   
gunzip <file.gzip> extract .gzip or .gz archive
zcat x.txt.gz >x.txt OR gzcat x.txt.gz > x.txt OR gunzip -c x.txt.gz > x.txt extract gzip without deleting archive
tar cvfz <archive.name.tar.gz> <file.name.1 file.name.2 ...> create tar.gz archive
tar xvfz <file.tar.gz> extract .tar.gz archive
tar xvf <file.tar> extract .tar archive
zip -r <zip-name.zip> <directory-to-zip> zip a directory
zip <zip-name.zip> <file1> <file2> ... zip multiple files into archive
unzip <zip-name.zip> unzip a .zip archive
   
/usr/local/sbin/haproxy -c -V -f /etc/haproxy/haproxy.cfg validate HAProxy configuration
service haproxy reload update HAProxy configuration
   
scp <file_name> <host>:/<path_on_host> copy file to remote host
   
`sslscan tests SSL/TLS enabled services to discover supported cipher suites