lsof -i列出，列出建立连接的连接数
[root@i-3pedyvud ~]# lsof -i|grep "ESTABLISHED"
dockerd 683 root 19u IPv4 26054 0t0 TCP i-3pedyvud:44964->i-3pedyvud:2377 (ESTABLISHED)
dockerd 683 root 21u IPv6 26055 0t0 TCP i-3pedyvud:2377->i-3pedyvud:44964 (ESTABLISHED)
sshd 1127 root 3u IPv4 26559 0t0 TCP i-3pedyvud:ssh->cde.gkmang.cn:45432 (ESTABLISHED)
列出建立连接的连接数
[root@i-3pedyvud ~]# netstat -ano|grep "ESTABLISHED"
tcp 0 0 10.140.19.9:44964 10.140.19.9:2377 ESTABLISHED off (0.00/0/0)
tcp 0 36 10.140.19.9:22 36.41.188.74:45432 ESTABLISHED on (0.26/0/0)
tcp6 0 0 10.140.19.9:2377 10.140.19.9:44964 ESTABLISHED off (0.00/0/0)
[root@i-3pedyvud ~]#
[root@i-3pedyvud ~]# lsof -i :22
COMMAND PID USER FD TYPE DEVICE SIZE/OFF NODE NAME
sshd 556 root 3u IPv4 23148 0t0 TCP *:ssh (LISTEN)
sshd 556 root 4u IPv6 23150 0t0 TCP *:ssh (LISTEN)
sshd 1127 root 3u IPv4 26559 0t0 TCP i-3pedyvud:ssh->cde.gkmang.cn:45432 (ESTABLISHED)
[root@i-3pedyvud ~]#
[root@i-3pedyvud ~]# lsof -i :8443|grep "ESTABLISHED"
httpd 818 apache 14u IPv6 103709 0t0 TCP i-3pedyvud:pcsync-https->cde.gkmang.cn:47817 (ESTABLISHED)
httpd 8449 apache 14u IPv6 103643 0t0 TCP i-3pedyvud:pcsync-https->cde.gkmang.cn:47796 (ESTABLISHED)
httpd 19127 apache 14u IPv6 102677 0t0 TCP i-3pedyvud:pcsync-https->cde.gkmang.cn:47763 (ESTABLISHED)
httpd 19212 apache 14u IPv6 103765 0t0 TCP i-3pedyvud:pcsync-https->cde.gkmang.cn:47825 (ESTABLISHED)
httpd 19463 apache 14u IPv6 103763 0t0 TCP i-3pedyvud:pcsync-https->cde.gkmang.cn:47823 (ESTABLISHED)
通过进程查找建立连接的
[root@i-3pedyvud ~]# lsof -i|grep "httpd"|grep "ESTABLISHED"|grep "cde.gkmang.cn"
httpd 818 apache 14u IPv6 103709 0t0 TCP i-3pedyvud:pcsync-https->cde.gkmang.cn:47817 (ESTABLISHED)
httpd 8449 apache 14u IPv6 103643 0t0 TCP i-3pedyvud:pcsync-https->cde.gkmang.cn:47796 (ESTABLISHED)
httpd 19127 apache 14u IPv6 102677 0t0 TCP i-3pedyvud:pcsync-https->cde.gkmang.cn:47763 (ESTABLISHED)
httpd 19141 apache 14u IPv6 103913 0t0 TCP i-3pedyvud:pcsync-https->cde.gkmang.cn:47836 (ESTABLISHED)
httpd 19463 apache 14u IPv6 103763 0t0 TCP i-3pedyvud:pcsync-https->cde.gkmang.cn:47823 (ESTABLISHED)
查找文件对应的进程 （yum install -y psmisc）
[root@i-3pedyvud ~]# fuser -u /usr/sbin/httpd
/usr/sbin/httpd: 27081e(root) 27082e(apache) 27083e(apache) 27084e(apache) 27086e(apache) 27087e(apache) 27579e(apache) 27617e(apache) 28879e(apache)
[root@i-3pedyvud ~]# lsof /usr/sbin/httpd
COMMAND PID USER FD TYPE DEVICE SIZE/OFF NODE NAME
httpd 27081 root txt REG 253,1 523648 12702778 /usr/sbin/httpd
httpd 27082 apache txt REG 253,1 523648 12702778 /usr/sbin/httpd
httpd 27083 apache txt REG 253,1 523648 12702778 /usr/sbin/httpd
httpd 27084 apache txt REG 253,1 523648 12702778 /usr/sbin/httpd
httpd 27086 apache txt REG 253,1 523648 12702778 /usr/sbin/httpd
httpd 27087 apache txt REG 253,1 523648 12702778 /usr/sbin/httpd
httpd 27579 apache txt REG 253,1 523648 12702778 /usr/sbin/httpd
httpd 27617 apache txt REG 253,1 523648 12702778 /usr/sbin/httpd
httpd 28879 apache txt REG 253,1 523648 12702778 /usr/sbin/httpd
[root@i-3pedyvud ~]#
查找程序对应的连接
[root@i-3pedyvud ~]# netstat -atlunp|grep httpd
tcp 0 0 10.140.19.9:38832 10.140.19.9:3306 ESTABLISHED 27084/httpd
tcp 0 0 10.140.19.9:38834 10.140.19.9:3306 ESTABLISHED 27082/httpd
tcp 0 0 10.140.19.9:38836 10.140.19.9:3306 ESTABLISHED 27083/httpd
tcp6 0 0 :::8443 :::* LISTEN 619/httpd
tcp6 0 0 :::8030 :::* LISTEN 619/httpd
tcp6 0 0 10.140.19.9:8443 36.41.188.74:48607 ESTABLISHED 27083/httpd
tcp6 0 0 10.140.19.9:8443 36.41.188.74:48609 ESTABLISHED 27617/httpd
tcp6 0 0 10.140.19.9:8443 36.41.188.74:48603 ESTABLISHED 27084/httpd
tcp6 0 1898 10.140.19.9:8443 36.41.188.74:48602 FIN_WAIT1 619/httpd
tcp6 0 0 10.140.19.9:8443 36.41.188.74:48611 ESTABLISHED 27086/httpd
tcp6 0 0 10.140.19.9:8443 36.41.188.74:48605 ESTABLISHED 27082/httpd
[root@i-3pedyvud ~]#
[root@i-3pedyvud cron.daily]# lsof -i :8443
COMMAND PID USER FD TYPE DEVICE SIZE/OFF NODE NAME
httpd 619 apache 6u IPv6 107733 0t0 TCP *:pcsync-https (LISTEN)
httpd 3104 apache 6u IPv6 107733 0t0 TCP *:pcsync-https (LISTEN)
httpd 3107 apache 6u IPv6 107733 0t0 TCP *:pcsync-https (LISTEN)
httpd 27081 root 6u IPv6 107733 0t0 TCP *:pcsync-https (LISTEN)
httpd 27083 apache 6u IPv6 107733 0t0 TCP *:pcsync-https (LISTEN)
httpd 27084 apache 6u IPv6 107733 0t0 TCP *:pcsync-https (LISTEN)
httpd 27086 apache 6u IPv6 107733 0t0 TCP *:pcsync-https (LISTEN)
httpd 27087 apache 6u IPv6 107733 0t0 TCP *:pcsync-https (LISTEN)
httpd 27579 apache 6u IPv6 107733 0t0 TCP *:pcsync-https (LISTEN)
httpd 27617 apache 6u IPv6 107733 0t0 TCP *:pcsync-https (LISTEN)
httpd 28879 apache 6u IPv6 107733 0t0 TCP *:pcsync-https (LISTEN)
[root@i-3pedyvud cron.daily]# ls -l /proc/27081/fd/6
lrwx------ 1 root root 64 1月 3 16:41 /proc/27081/fd/6 -> socket:[107733]
[root@i-3pedyvud cron.daily]#
