Linux networking.md

Collection of Linux tools to deal with network issues

nmap.sh

# nmap - Network exploration tool and security / port scanner
# ----------------------------------------------------------------------------

# List ports in use
nmap localhost
nmap 192.168.11.22

# endless loop
watch -n1 'sudo netstat -taupn'

send events to collector

# Netcat is a simple Unix utility which reads and writes data across network connections
# ----------------------------------------------------------------------------

# Test if a port on a remote system is reachable
#     Will output 0 if port 123 is open, and 1 if it's closed.
nc 127.0.0.1 123 < /dev/null; echo $?     

# Send arbitrary string to remote connection
echo "<13>1 - - - - [b9d9a9c4-11d5-4b15-844f-c7d0e4353983@41058] `date` This is the heartbeat message" | netcat -q 1 targethost 514

echo "<13>1 - - - - [b9d9a9c4-11d5-4b15-844f-c7d0e4353983@41058] `date` ping" | nc -vv -w 4 targethost 514

ssh

# Connectting to office VPN
ssh-add ~/.ssh/id_rsa
ssh -A vkroz@vpn.office.loggly.org

wireshark.sh

# Other useful stuff
wireshark
tcpdump