Look at the configuration file first:
2Auto Lo3iface Lo inet loopback4Auto Eth05iface eth0 inet static6Address10.21.238.238 7Netmask255.255.255.0 8Broadcast10.21.238.255 9Gateway10.21.238.1 TenAuto br100 Oneiface br100 inet static Abridge_ports eth0 -BRIDGE_STP off -Bridge_maxwait0 theBridge_fd0 -Address10.21.238.238 -Netmask255.255.255.0 -Broadcast10.21.238.255 +Gateway10.21.238.1
Then you may not see br100 information, which requires service networking restart && ifup br100 or restarting the computer.
Installing bridge-utils at the same time can view current bridge information through Brctl Show
[Email protected]:/image# brctl showbridge name ID STP enabled interfacesbr100 8000 . a0d3c1247ba0 no eth0 vnet0virbr0 8000. fe54814bd460 Yes Vnet1
You can see that after I use KVM to create a new virtual machine, the current host network information virtual machine VNET0 network card and the network of the computer are bridged to the local br100 bridge, so that the virtual machine can be connected to the network. The vnet1 corresponds to another NIC of the virtual machine, which is connected using the default bridge.
Network Bridge configuration for KVM-installed hosts for virtual machines