Linux Commands

Extract the contents from archive.tar.gz in the current directory $ tar xzvf archive.tar.gz
Download a file from web with wget $ wget https://raw.githubusercontent.com/svenfuchs/rails-i18n/master/rails/locale/en.yml
Download a file with basic authentication using wget (both HTTP and FTP) $ wget --user=USERNAME --password=PASS https://xxxx
Perform basic DNS lookups with the specified name server (e.g. 8.8.8.8 ) $ dig @8.8.8.8 www.wazaterm.com
Find files modified in the last 10 days from current directory and show the detailed list $ find . -mtime -10 -ls
Print all system information $ uname -a
Print kernel release information $ uname -r
Display how long the system has been running and load $ uptime
How to PUT JSON with curl $ curl -X PUT -H "Content-Type: application/json" -d '{"id": "1", "key": "value"}' localhost:3000/api/v1/users
Authenticate with JWT token using curl $ curl -X POST -H 'Accept: application/json' -H "Authorization: Bearer ${TOKEN}" -d '{"id": "1"}' localhost:3000/api/v1/users
How to prevent SSH from timing out $ ssh -o "ServerAliveInterval 60"
Check listening ports with netstat $ sudo netstat -tunlp
Copy home directory - Copy the content of /home/username to current directory (assuming you are in /home/username) $ rsync -avz username@s15.wazaterm.com:/home/username/ .
Create a tar archive file archive.tar for a directory backup in current working directory $ tar cvf archive.tar ./backup/
Extract the contents from archive.tar in the current directory $ tar xvf archive.tar
Extract the contents from archive.tar in /tmp directory $ tar xvf archive.tar -C /tmp
Add execute permission to foo.sh $ chmod u+x foo.sh
Change the owner of the file, foo.txt, to root $ chmod root foo.txt
Change the owner of the file, foo.txt, to root and the group owner to sudousers $ chmod root:sudousers foo.txt
Change the owner of the files to root against files under the directory, linux, recursively $ chown -R root linux/
Display all of the messages in the ring buffer $ dmesg
Display device info as the human-readable output $ dmesg -H
Search for SPF records $ dig wazaterm.com txt
Perform IPv6 DNS lookups $ dig AAAA dns.google
Get hostname from IP Address(Reverse lookup) $ dig -x 8.8.8.8
Check MX record of the domain $ dig gmail.com MX
Perform basic DNS lookups $ dig www.wazaterm.com
Check if a host is up with IPv6 address $ ping -6 www.google.com
Check whether a remote host is up with 3 seconds interval and 5 times $ ping -c 5 -i 3 www.google.com
Show unixtime $ date +%s