CentOS7路由、端口和服务排障常用命令

1. ip route 显示主机基本路由信息

~]# ip route

default via 172.25.0.254 dev eth0 proto static metric 1024

172.25.0.0/24 dev eth0 proto kernel scope link src 172.25.0.11

172.25.253.254 via 172.25.0.254 dev eth0 proto static metric 1

2. traceroute / tracepath 追踪远程主机UDP数据包路径

traceroute 默认追踪UDP数据包，选项 -I 可追踪 ICMP的数据包，-T可追踪TCP数据包

~]# tracepath www.baidu.com

1?: [LOCALHOST] pmtu 1500

1: gateway 4.109ms

1: gateway 3.545ms

2: 192.168.0.2 0.320ms

3: 210.206.46.79 6.380ms

4: 10.255.88.241 1.432ms

5: 10.255.33.141 1.131ms

6: 10.255.30.49 4.399ms

7: 10.255.28.173 2.054ms

8: 124.205.98.69 1.810ms

9: 14.197.243.133 1.918ms

10: 14.197.250.170 2.636ms

11: 182.61.253.119 3.439ms

Too many hops: pmtu 1500

Resume: pmtu 1500

3. ss 与netstat功能相当

ss与netstat 选项

-n 显示接口和端口的编号，且不显示名称

-t 显示TCP套接字

-u 显示TCP套接字

-l 仅显示侦听中的套接字

-a 显示所有套接字，包括侦听中和已经建立的

~]# ss -ta

State Recv-Q Send-Q Local Address:Port Peer Address:Port

LISTEN 0 128 *:https *:*

LISTEN 0 5 *:ideafarm-door *:*

LISTEN 0 5 *:5901 *:*

LISTEN 0 128 *:sunrpc *:*

LISTEN 0 128 *:6001 *:*

LISTEN 0 128 127.0.0.1:8307 *:*

LISTEN 0 5 192.168.122.1:domain *:*

LISTEN 0 128 *:ssh *:*

LISTEN 0 128 127.0.0.1:ipp *:*

LISTEN 0 100 127.0.0.1:smtp *:*

ESTAB 0 0 192.168.96.254:ssh 192.168.101.251:53439

LISTEN 0 128 :::https :::*

LISTEN 0 5 :::ideafarm-door :::*

LISTEN 0 5 :::5901 :::*

LISTEN 0 128 :::sunrpc :::*

LISTEN 0 128 :::6001 :::*

LISTEN 0 128 ::1:8307 :::*

LISTEN 0 128 :::ssh :::*

LISTEN 0 128 ::1:ipp :::*

LISTEN 0 100 ::1:smtp :::*