-- list the open ports and the process that owns them
root# lsof -i
-- Old style netstat
root#netstat -tulpn | less
-- See which process is bound to port 3872
root# lsof -i:3872
Example--> root# lsof -i
CMD PID USER FD TYPE DEVICE SIZE NODE NAME
oracle 354 oracle 19u IPv4 2894616637 UDP 169.254.111.254:49430
oracle 354 oracle 22u IPv4 2894616638 UDP localhost.localdomain:31489
oracle 354 oracle 24u IPv4 2894616640 UDP 169.254.111.254:65139
oracle 356 oracle 19u IPv4 2894616648 UDP 169.254.111.254:52799
oracle 356 oracle 22u IPv4 2894616650 UDP localhost.localdomain:10267
oracle 356 oracle 24u IPv4 2894616652 UDP 169.254.111.254:61528
oracle 358 oracle 19u IPv4 2894616669 UDP 169.254.111.254:31016
oracle 358 oracle 22u IPv4 2894616670 UDP localhost.localdomain:65134
oracle 358 oracle 24u IPv4 2894616671 UDP 169.254.111.254:11811
oracle 405 oracle 19u IPv4 501716719 UDP 169.254.111.254:49059
oracle 405 oracle 22u IPv4 501716720 UDP localhost.localdomain:39383
oracle 405 oracle 24u IPv4 501716724 UDP 169.254.111.254:55199
oracle 407 oracle 19u IPv4 501716638 UDP 169.254.111.254:59708
oracle 407 oracle 22u IPv4 501716646 UDP localhost.localdomain:24933
oracle 407 oracle 24u IPv4 501716655 UDP 169.254.111.254:63862
oracle 488 oracle 19u IPv4 3821891154 UDP 169.254.111.254:9376
Example -> netstat -tulpn | less
Proto Recv-Q Send-Q Local Address Foreign Address State PID/Program name
tcp 0 0 127.0.0.1:2016 0.0.0.0:* LISTEN 16794/oraagent.bin
tcp 0 0 0.0.0.0:736 0.0.0.0:* LISTEN 14549/rpc.mountd
tcp 0 0 0.0.0.0:59936 0.0.0.0:* LISTEN -
tcp 0 0 0.0.0.0:2049 0.0.0.0:* LISTEN -
tcp 0 0 0.0.0.0:643 0.0.0.0:* LISTEN 14455/rpc.rquotad
tcp 0 0 127.0.0.1:199 0.0.0.0:* LISTEN 14324/snmpd
tcp 0 0 127.0.0.1:7017 0.0.0.0:* LISTEN 16455/p_ctmat
tcp 0 0 127.0.0.1:57386 0.0.0.0:* LISTEN 11154/pbx_exchange
tcp 0 0 0.0.0.0:139 0.0.0.0:* LISTEN 14752/smbd
tcp 0 0 0.0.0.0:683 0.0.0.0:* LISTEN 11101/rpc.statd
tcp 0 0 0.0.0.0:49133 0.0.0.0:* LISTEN 16815/gpnpd.bi
Example : root# lsof -i:2016
COMMAND PID USER FD TYPE DEVICE SIZE NODE NAME
oraagent. 16794 oracle 40u IPv4 308843 TCP localhost.localdomain:bootserver (LISTEN)
