tcpdump 用法
-i eth0 表示网卡
-A 表示转为 ascii 码
-n 表示不要转域名，用 ip 就好
host 后面加 IP 地址
查看 nginx 是长连接还是短连接：
[root@nginx01 ~]# tcpdump -i eth0 -A host 192.168.156.44 -n | grep HTTP
tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
listening on eth0, link-type EN10MB (Ethernet), capture size 262144 bytes
.oJ&…ePOST /v2/story/comic/xxx/top HTTP/1.1
…}.oJ&HTTP/1.1 200 OK
.oN…..POST /v1/story/xxx HTTP/1.1
…..oN.HTTP/1.1 200 OK
.oN….:POST /v1/story/xxx HTTP/1.1
…[.oN.HTTP/1.1 200 OK
.oR….BPOST /v2/story/comic/xxx/top HTTP/1.1
.oS….MPOST /v1/story/xxx HTTP/1.1
…`.oR.HTTP/1.1 200 OK
结果:
HTTP/1.1 实锤