Linux command
============NETSTAT============= On .80 machine tcp6 0 0 10.10.4.80:44016 15.15.0.1:3083 ESTABLISHED Here local port 10.10.4.80:44016 is connected with remote 15.15.0.1:3083 On .99 machine tcp6 0 0 15.15.0.1:3083 10.10.4.80:44016 ESTABLISHED tcp6 0 0 15.15.0.1:3083 :::* LISTEN and is listening from any connection from any ip and port from outside, so its a server socket on .99 ===================TCP DUMP================ tcpdump -vv -X -i em3 'port 44016' -w dump.log ========================DF =================== Filesystem Size Used Avail Use% Mounted on devtmpfs 252G 0 252G 0% /dev tmpfs 252G 4.0K 252G 1% /dev/shm tmpfs 252G 652M 252G 1% /run tmpfs 252G 0 252G 0% /sys/fs/cgroup /dev/mapper/centos-root 1.8T 4.8G 1.7T 1% / /dev/loop0 1.9G 6.1M 1.7G 1% /sr