我的KVM主机（Ubuntu 16.04）发生了一些事情。
我有一些虚拟机configuration为使用br0因此它们在局域网上显示为独立的机器，并拥有自己的IP。
他们通过DHCP从路由器获取IP。 一切都好。
但当然，它停止了工作，我不明白为什么。 br0仍然存在，但机器永远无法获得DHCP租约。 主机仍然有连接。 如果我将机器切换到NAT，他们可以访问networking。 但不能与br0 。
这里是主机上的/etc/network/interfaces ：
# This file describes the network interfaces available on your system # and how to activate them. For more information, see interfaces(5). source /etc/network/interfaces.d/* # The loopback network interface auto lo iface lo inet loopback # The primary network interface # auto enp4s0 # iface enp4s0 inet manual # VMs bridge auto br0 iface br0 inet dhcp bridge_ports enp4s0 bridge_stp off bridge_fd 0 bridge_maxwait 0
$ ip addr：
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1 link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 inet 127.0.0.1/8 scope host lo valid_lft forever preferred_lft forever inet6 ::1/128 scope host valid_lft forever preferred_lft forever 2: enp4s0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq master br0 state UP group default qlen 1000 link/ether 00:1d:09:0b:87:6d brd ff:ff:ff:ff:ff:ff inet6 fe80::21d:9ff:fe0b:876d/64 scope link valid_lft forever preferred_lft forever 3: br0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000 link/ether 00:1d:09:0b:87:6d brd ff:ff:ff:ff:ff:ff inet 192.168.1.129/24 brd 192.168.1.255 scope global br0 valid_lft forever preferred_lft forever inet6 fe80::21d:9ff:fe0b:876d/64 scope link valid_lft forever preferred_lft forever 4: br-0e57a29cd0f7: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc noqueue state DOWN group default link/ether 02:42:2b:9a:39:d6 brd ff:ff:ff:ff:ff:ff inet 172.18.0.1/16 scope global br-0e57a29cd0f7 valid_lft forever preferred_lft forever 5: docker0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default link/ether 02:42:ed:8f:cb:c1 brd ff:ff:ff:ff:ff:ff inet 172.17.0.1/16 scope global docker0 valid_lft forever preferred_lft forever inet6 fe80::42:edff:fe8f:cbc1/64 scope link valid_lft forever preferred_lft forever 7: veth44c7e80@if6: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue master docker0 state UP group default link/ether 3e:61:3e:be:b2:8e brd ff:ff:ff:ff:ff:ff link-netnsid 0 inet6 fe80::3c61:3eff:febe:b28e/64 scope link valid_lft forever preferred_lft forever 8: virbr0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc noqueue state DOWN group default qlen 1000 link/ether 52:54:00:41:79:0f brd ff:ff:ff:ff:ff:ff inet 192.168.122.1/24 brd 192.168.122.255 scope global virbr0 valid_lft forever preferred_lft forever 9: virbr0-nic: <BROADCAST,MULTICAST> mtu 1500 qdisc pfifo_fast master virbr0 state DOWN group default qlen 1000 link/ether 52:54:00:41:79:0f brd ff:ff:ff:ff:ff:ff
$ brctl show
bridge name bridge id STP enabled interfaces br-0e57a29cd0f7 8000.02422b9a39d6 no br0 8000.001d090b876d no enp4s0 docker0 8000.0242ed8fcbc1 no veth44c7e80 virbr0 8000.52540041790f yes virbr0-nic
$ ip路由列表
default via 192.168.1.1 dev br0 172.17.0.0/16 dev docker0 proto kernel scope link src 172.17.0.1 172.18.0.0/16 dev br-0e57a29cd0f7 proto kernel scope link src 172.18.0.1 linkdown 192.168.1.0/24 dev br0 proto kernel scope link src 192.168.1.129 192.168.122.0/24 dev virbr0 proto kernel scope link src 192.168.122.1 linkdown
用虚拟机启动brctl show：
bridge name bridge id STP enabled interfaces br-0e57a29cd0f7 8000.02422b9a39d6 no br0 8000.001d090b876d no enp4s0 vnet0 docker0 8000.0242ed8fcbc1 no veth44c7e80 virbr0 8000.52540041790f yes virbr0-nic
$ ip地址显示dev vnet0
13: vnet0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast master br0 state UNKNOWN group default qlen 1000 link/ether fe:54:00:81:08:d0 brd ff:ff:ff:ff:ff:ff inet6 fe80::fc54:ff:fe81:8d0/64 scope link valid_lft forever preferred_lft forever
我不知道该怎么做。 我尝试删除并重新安装kvm + qemu，删除并重新创build桥，创build一个新的虚拟机br0 …绝对没有变化。