路由命令route

Linux下查询路由表查看路由表 (Mac下查询路由表netstat -nr)
```
$ route -n
$ netstat -nr
```

路由表解读

$ netstat -nr
 Kernel IP routing table
 Destination:     Gateway         Genmask         Flags   MSS Window  irtt Iface
 172.16.1.0      0.0.0.0         255.255.255.0   U         0 0          0 eth0
 169.254.0.0     0.0.0.0         255.255.0.0     U         0 0          0 eth0
 0.0.0.0         172.16.1.247    0.0.0.0         UG        0 0          0 eth0

 Destination: 目的地网段
 Gateway: 网关
 Genmask: 目的地网络掩码
 Flags:   U (route is up)
          H (target is a host)
          G (use gateway)
          R (reinstate route for dynamic routing)
          D (dynamically installed by daemon or redirect)
          M (modified from routing daemon or redirect)
          A (installed by addrconf)
          C (cache entry)
          !  (reject route)
 MSS: Default maximum segement size for TCP
 Window: Default window size for TCP
irtt: Initial  RTT  (Round  Trip  Time)
Iface: interface

路由表缓存查看
```
$ route -Cen
```

添加路由

# route add -net 10.38.0.0 netmask 255.255.0.0 gw 192.168.100.1
# route add -host 192.168.98.101 gw 192.168.99.1

设置网关

# route add default gw 192.168.99.254
# route add -net 0.0.0.0 netmask 0.0.0.0 gw 192.168.99.254

删除路由

# route del default gw 192.168.98.254
# route add -net 192.168.99.0 netmask 255.255.255.0 gw 192.168.98.254

参考资料