1.ip route show $ ip route showdefault via 192.168.217.2 dev eth0 metric 100 192.168.122.0/24 dev virbr0 proto kernel scope link src 192.168.122.1 192.168.217.0/24 dev eth0 proto kernel scope link src 192.168.217.129 eth0 网关地址为192
          1. ip route show
$ ip route show
default via 192.168.217.2 dev eth0  metric 100 
192.168.122.0/24 dev virbr0  proto kernel  scope link  src 192.168.122.1 
192.168.217.0/24 dev eth0  proto kernel  scope link  src 192.168.217.129eth0 网关地址为 192.168.217.2 
2. route -n or netstat -rn
$ route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
0.0.0.0         192.168.217.2   0.0.0.0         UG    100    0        0 eth0
192.168.122.0   0.0.0.0         255.255.255.0   U     0      0        0 virbr0
192.168.217.0   0.0.0.0         255.255.255.0   U     0      0        0 eth0eth0 网关地址为 192.168.217.2 
3. traceroute www.baidu.com
$ traceroute www.baidu.com
traceroute to www.baidu.com (119.75.218.77), 30 hops max, 60 byte packets
 1  localhost (192.168.217.2)  0.607 ms  0.546 ms  1.379 ms
 2  * * *
 3  * * *
 4  * * *
 5  * * *
 6  * * *
 7  * * *
 8  * * *
 9  * * *
10  * * *第一跳的地址就是网关地址 
参考资料
Centos/Linux下如何查看网关地址/Gateway地址?
