Some commands I commonly use

  1. Find out available space:
    df -h --total
    or
    System monitor > Filesystems tab
  2. Directory or space with their usage:
    du -a -d 1 /home/ | sort -n -r | head -n 5
  3. Find folder with specific name
    find /path/to/look/up -type d -name "folder name"
  4. Linux version:
    lsb_release -a
  5. Cisco IOS doesn’t accept ssh:
    ssh -oKexAlgorithms=+diffie-hellman-group1-sha1 username@target-hostname/IP
  6. Find specific word: (source: link)
    grep -rnw '/path/to/somewhere/' -e 'pattern'
    -r
    or -R is recursive,
    -n is line number, and
    -w stands for match the whole word.
    -l (lower-case L) can be added to just give the file name of matching files.
    -e is the pattern used during the search