Useful Linux commands, with no particular order

sudo lsof -i:port

sudo kill -9 PID

du -hs .

df -h

More info: https://www.ssh.com/ssh/tunneling/example/

ssh-copy-id user@server

ssh -L local-port:localhost:remote-port user@server -N

Note: AllowTcpForwarding and PermitOpen have to be enabled in /etc/ssh/sshd_config

ssh -N -T -R local-port:localhost:remote-port user@server

• -N Do not execute a remote command. This is useful for just forwarding ports.
• -T Disable pseudo-terminal allocation.
• -R Specifies that connections to the given TCP port or Unix socket on the remote (server) host are to be forwarded to the local side.

scp -r /folder/to/upload user@server:/destination/on/server

tar -czvf file.tar.gz file/or/folder/to/tar/

• -c create
• -z gzip
• -v verbose
• -f filename

tar -xvf file.tar.gz

• -x extract
• -v verbose
• -f filename

gpg -c --cipher-algo AES256 file/to/encrypt

You will be asked to enter a password

gpg file/to/decrypt

You will be asked to enter a password

More: https://gist.github.com/mikecrittenden/fe02c59fed1aeebd0a9697cf7e9f5c0c

wget \
     --mirror \ # Makes (among other things) the download recursive.
     --page-requisites \ # Get all assets/elements (CSS/JS/images).
     --adjust-extension \ # Save files with .html on the end.
     --span-hosts \ # Include necessary assets from offsite as well.
     --convert-links \ # Update links to still work in the static version.
     --restrict-file-names=windows \ # Modify filenames to work in Windows as well.
     --domains yoursite.com \ # Do not follow links outside this domain.
     --no-parent \ # Don't follow links outside the directory you pass in.
         yoursite.com/whatever/path # The URL to download

openssl req \
  -x509 \
  -newkey rsa:4096 \
  -sha256 \
  -keyout mykeyname.key \
  -out mycertname.pem \ 
  -days 365 
  -nodes # only if you need no password