1、netstat -an | awk ‘/^tcp/ {++S[$NF]} END {for(a in S) print a, S[a]}’
查看tcp连接数状态
2、sudo netstat -antp |wc -l
查看所有TCP连接数
3、 sudo /usr/sbin/tcpdump -p tcp and host 172.16.136.180
tcpdump查看tcp协议的包：
16:12:28.632819 IP 172.16.136.180.28227 > 172.16.140.154.redwood-broker: S 1596666623:1596666623(0) win 14600
16:12:28.653821 IP 172.16.140.154.redwood-broker > 172.16.136.180.28227: S 3715298672:3715298672(0) ack 1596666624 win 5840
16:12:28.632992 IP 172.16.136.180.28227 > 172.16.140.154.redwood-broker: . ack 1 win 29
16:12:28.633112 IP 172.16.136.180.28227 > 172.16.140.154.redwood-broker: P 1:267(266) ack 1 win 29
16:12:28.633125 IP 172.16.140.154.redwood-broker > 172.16.136.180.28227: . ack 267 win 54
16:12:28.634689 IP 172.16.140.154.redwood-broker > 172.16.136.180.28227: P 1:538(537) ack 267 win 54
16:12:28.634712 IP 172.16.140.154.redwood-broker > 172.16.136.180.28227: F 538:538(0) ack 267 win 54
16:12:28.634911 IP 172.16.136.180.28227 > 172.16.140.154.redwood-broker: . ack 538 win 31
16:12:28.635076 IP 172.16.136.180.28227 > 172.16.140.154.redwood-broker: F 267:267(0) ack 539 win 31
16:12:28.635086 IP 172.16.140.154.redwood-broker > 172.16.136.180.28227: . ack 268 win 54
4、sudo traceroute -T -q 10 -w 5 172.16.140.154
查看网络跳包