KVM虚拟机开机未自动启动br0网卡故障记录

1. 环境查看
   系统环境

# cat /etc/kylin-release 
Kylin Linux Advanced Server release V10 (Lance)
# uname -a
Linux KylinServer003206 4.19.90-52.46.v2207.ky10.x86_64 #3 SMP Fri Mar 14 11:13:11 UTC 2025 x86_64 x86_64 x86_64 GNU/Linux

2. 故障现象
   KVM虚拟机需要使用虚拟绑定网卡br0已经设置开机自启动，但是重启后未设置好ip地址
   查看系统日志发现以下报错信息

# cat messages |grep rc.local
May 22 08:07:28 KylinServer003206 systemd[1]: Starting /etc/rc.d/rc.local Compatibility...
May 22 08:07:28 KylinServer003206 systemd[1]: Started /etc/rc.d/rc.local Compatibility.
May 22 08:07:28 KylinServer003206 rc.local[3082]: RTNETLINK answers: Cannot assign requested address

3. 故障原因
   绑定的网卡没有设置自启动
4. 故障修复
   修改绑定网卡的配置
   把ONBOOT=no修改为yes
   因为这个是绑定网卡所以可以设置成dhcp也可以设置成固定ip

# cat /etc/sysconfig/network-scripts/ifcfg-enp136s0f3 
NAME=enp136s0f3
DEVICE=enp136s0f3
TYPE=Ethernet
DEFROUTE=yes
ONBOOT=yes
BOOTPROTO=dhcp
#BOOTPROTO=static
#IPADDR=192.168.3.201
#PREFIX=24
#GATEWAY=192.168.3.2
#DNS1=192.168.3.2
#DNS1=114.114.114.114

查看开机启动脚本

# cat /usr/local/bin/start.sh
#!/bin/bash
brctl addbr br0 && brctl addif br0 enp136s0f3 && ip addr del dev enp136s0f3 192.168.3.201/24 && ifconfig br0 192.168.3.201/24 up && route add default gw 192.168.3.2

重启系统查看设置是否生效

# init 6