Useful Linux snippets
Some simple commands for bash that have been helpful in the past.
# Adding a remote machine on docker-machine
# Note we specify btrfs as we are using that driver in docker for our remote machine
docker-machine -D create --driver generic --generic-ip-address <ip> --generic-ssh-key /a/b/x.pem --engine-storage-driver btrfs name-here
# Search text, ignore case
grep -ri TEXT .
# Is port 8080 being used
netstat -vatn | grep 8080
# Give the last 500 lines of a log and follow it
tail -500f file.txt
# Which process is listening on port
netstat -tulpn
# Who is using all the ram?
ps --everyone --format=pid,vsz,comm= | sort --numeric-sort --key=2
# Change prompt
echo $PS1
\h:\W \u\$
# Replace in VI
:%s/search_string/replacement_string/g
# View packets
tcpdump -nS
# time process living
ps -p $$ -o etime=
# list all iptables rules
iptables --list
#restart docker
sudo service docker restart
# tcpdump
sudo tcpdump host 172.17.0.3 -nS -i docker0
# Run loop
while sleep 1; do sudo netstat -tulpn | grep 6100; done
# check what port range
sysctl -n net.ipv4.ip_local_port_range
# largest files in directory /var
du -a /var | sort -n -r | head -n 10