KVM虚拟机配置与主机同网段网络后无法联网的问题排查求助

我按照Ubuntu 22.04上KVM的安装配置步骤，做了一系列桥接网络的配置操作，但虚拟机还是无法连接到互联网，想请教下各位大佬问题出在哪？

我的操作步骤如下：

• 编辑Netplan网络配置文件：

  $ sudo vi /etc/netplan/01-netcfg.yaml
  

  配置内容如下（yaml格式）：

  network:
    ethernets:
      enp0s3:
        dhcp4: false
        dhcp6: false
    # add configuration for bridge interface
    bridges:
      br0:
        interfaces: [enp0s3]
        dhcp4: false
        addresses: [192.168.1.162/24]
        macaddress: 08:00:27:4b:1d:45
        routes:
          - to: default
            via: 192.168.1.1
            metric: 100
        nameservers:
          addresses: [4.2.2.2]
        parameters:
          stp: false
          dhcp6: false
    version: 2
  

• 应用Netplan配置：

  sudo netplan apply
  

• 查看当前网络接口状态，执行$ ip a得到如下输出：

  1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
      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: enp2s0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
      link/ether e4:54:e8:62:02:3e brd ff:ff:ff:ff:ff:ff
      inet 192.168.1.112/24 brd 192.168.1.255 scope global dynamic noprefixroute enp2s0
         valid_lft 5283sec preferred_lft 5283sec
      inet6 fe80::9431:8b2a:4a7b:29c8/64 scope link noprefixroute
         valid_lft forever preferred_lft forever
  4: virbr0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc noqueue state DOWN group default qlen 1000
      link/ether 52:54:00:68:0e:ff 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
  15: br0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
      link/ether 08:00:27:4b:1d:45 brd ff:ff:ff:ff:ff:ff
      inet 192.168.1.162/24 brd 192.168.1.255 scope global noprefixroute br0
         valid_lft forever preferred_lft forever
      inet6 fe80::a00:27ff:fe4b:1d45/64 scope link
         valid_lft forever preferred_lft forever
  17: vnet4: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue master br0 state UNKNOWN group default qlen 1000
      link/ether fe:54:00:b8:09:6a brd ff:ff:ff:ff:ff:ff
      inet6 fe80::fc54:ff:feb8:96a/64 scope link
         valid_lft forever preferred_lft forever
  

另外，我也在Virt Manager界面里设置了对应的虚拟网络接口，本以为步骤都没问题，但虚拟机还是没法联网，麻烦各位帮忙看看哪里出错了？谢谢！

备注：内容来源于stack exchange，提问作者丶 Limeー来夢 丶