Ubuntu KVM host network problems

Ubuntu KVM host network problems received an article: http://www.bkjia.com/ OS /201209/157166.html vacation back, continue to install KVM virtual machine. Suddenly, the host machine cannot be connected to the Internet. Finally found a solution in this article: The Key to http://askubuntu.com/questions/179508/kvm-bridged-network-not-working is that there is a row missing in the route table. The successfully configured route table is as follows: www.2cto.com [plain] # ip route list default via route dev br0 default via 10.112.18.1 dev br0 metric 100 10.112.18.0/24 dev br0 proto kernel scope link src route 192.168.122.0/24 dev virbr0 proto kernel scope link src 192.168.122.1 after my previous article is completed, there will be some strange phenomena: www.2cto.com 1. after you log on to the host from another machine through ssh, you will not be able to connect to the host after a while, and then ssh will not be able to log on until you restart the network service of the host machine. 2. the host machine cannot connect to the Internet. 3. this line is missing in the routing table: [plain] default via 10.112.18.254 dev br0 solution reference: The http://askubuntu.com/questions/179508/kvm-bridged-network-not-working executes the following command once, some will report an error message, but it doesn't matter. Www.2cto.com [plain] As an alternative you can disable the use of Ethernet and make sure that it does not have an IP address, and that there isn't a default route set up with ip route. then: sudo ifconfig eth0 0.0.0.0 up sudo brctl addbr br0 sudo brctl addif br0 eth0 sudo ifconfig br0 up sudo dhclient br0 & now returns to normal.