Ubuntu is an open source operating system for all users. Here Ubuntu/Linux basic and advanced commands for beginners and admins.
Ubuntu/Linux commands for Ubuntu users:
SYSTEM COMMANDS:
Below commands related to the system by using the terminal
uname -a — Display LINUX system information
uname -r — Display kernel release information
uptime — Show how long the system has been running + load
hostname — Show system hostname
hostname -i — Display the IP address of the host
last reboot — Show system reboot history
date — Show the current date and time
cal — Show this month calendar
whoami — Who you are logged in as
FILE COMMANDS:
Is -al –Display all information about files/ directories
pwd –Show the path of the current directory
mkdir directory-name –Create a directory
cp file l file 2 –Copy file l to file 2
cp -r dir 1 dir 2 –Copy dir 1 to dir 2, create dir 2 if it doesn’t exist
mv file l file 2 –Rename source to dest / move source to directory
touch file –Create or update file
cat > file –Place standard input into file
more file –Output contents of the file
head file –Output first 10 lines of file
tail file –Output last 10 lines of file
wc –print the number of bytes, words, and lines in files
xargs –Execute command lines from standard input.
rm file-name –Delete file
rm -r directory-name –Delete directory recursively
rm -f file-name –Forcefully remove file
rm -rf directory-name –Forcefully remove directory recursively
PROCESS RELATED COMMANDS:
ps –Display your currently active processes
pmap –Memory map of the process
top –Display all running processes
bg –Resumes suspended jobs without bringing them to the foreground
fg –Brings the most recent job to foreground
fg n –Brings job n to the foreground
kill pid –Kill process with mentioned pid id
kill all proc –Kill all processes named proc
pkill process-name –Send signal to a process with its name
ps aux | grep ‘telnet’ –Find all process id related to telnet process
NETWORK COMMANDS:
ifconfig — Display ip address in ubuntu
ip addr show –Display all network interfaces and ip address
ip address add 192.168.0.1 dev eth0 –Set IP address
mii-tool eth0 –Linux tool to show ethernet status
ping host –Send echo request to test
dig domain –Get DNS information for the domain
dig -x host –Reverse lookup host
host commandstech.com –Lookup DNS ip address for the name
hostname -i –Lookup local ip address
wget file –Download file
netstat -tupl –Listing all active listening ports.
INSTALL PACKAGE COMMANDS:
rpm -i pkg name.rpm –Install rpm based package
rpm -e pkg name –Remove package
HARDWARE COMMANDS:
dmesg –Detected hardware and boot messages
cat /proc/cpuinfo –CPU model
cat /proc/meminfo –Hardware memory
cat /proc/interrupts –List the number of inturrepts per CPU per I/O device
lshw –Display information on hardware configuration of the system
lsblk –Displays block device-related information in LINUX
free -m –Used and free memory(-m for MB)
lspci -tv –Show PCI devices
lsusb -tv –Show USB divices
dmidecode –Show hardware info from the BIOS
USER COMMANDS:
id –Show the active user id with login and group
last –Show last logins on the system
who –Show who is logged on the system
usermod –Modify user information.
groupadd admin –Add group “admin”
useradd -c “Sam Tomshi” –g admin -m sam #Create user “sam”
userdel sam –Delete user sam
adduser sam –Add user “sam”
FILE PERMISSION RELATED COMMANDS:
chmod octal file-name –Change the permissions of file to octal
chmod 777 /data/test.c –Set rwx permission for owner,group,world
chmod 755 /data/test.c –Set rwx permission for owner,rx for group and world
chown owner-user file –Change owner of the file
chown owner-user:owner-group file-name –Change owner and group owner of the file
chown owner-user:owner-group directory –Change owner and group owner of the directory.
COMPRESSION/ARCHIVES COMMANDS:
tar cf home.tar home –Create tar named home.tar containg home
tar xf file.tar –Extract the files from file.tar
tar czf file.tar.gz files –Create a tar with gzip compression
gzip file –Compress file and renames it to file.gz
DISC USAGE COMMANDS:
df -h –Show free space on mounted filesystems
df -i –Show free inodes on mounted filesystems
fdisc -l –Show discs partitions sizes and types
du -ah –Display disc usage in human readable form
du -sh –Display total dosc usage on the current directory
findmnt –Displays target mount point for all filesystem
mount device-path mount-point –Mount a device
DIRECTORY TRAVERSE COMMANDS:
cd .. –To go up one level of the directory tree
cd –goto $HOME directory
cd/test –Change to/Test directory