Shell & Unix

Shell and Unix notes

How to make tarballs

Unix command tar
bundles files without compression.
see tar documentation

  • Supported in Unix environments.
  • Can also gzip

Modes

  • -c create an archive (files to archive, archive from files)
  • -x extract an archive (archive to files, files from archive)

Options

  • -f FILE name of archive - must specify unless using tape drive for archive
  • -v be verbose, list all files being archived/extracted
  • -z create/extract archive with gzip/gunzip
  • -j create/extract archive with bzip2/bunzip2
  • -J create/extract archive with XZ

To compress

Compress (gzip) and package (tar) the directory myfiles to create myfiles.tar.gz:

tar -czvf myfiles.tar.gz myfiles/

To uncompress

Uncompress (gzip) and unpack compressed package, extracting contents from myfiles:

tar -xzvf myfiles.tar.gz

How to check your memory processes

Top memory consumers

  • top

Check how much memory is used vs free

  • free -m

Check all the memory each process is consuming

  • ps aux --sort -rss | head -n 15

kill an unresponsive process on Unix

  • ps aux | grep <service name>
  • find its process id (PID)
  • kill -9 PID

Check port use

  • sudo netstat -naplt | grep 8080

Check Node traffic on specific port

  • sudo tcpdump -A -i lo port 2354

to get unix my ip address

  1. echo `ifconfig eth0 2>/dev/null|awk '/inet addr:/ {print $2}'|sed 's/addr://'`

ssh

Secure shell