在尝试将虚拟机的ip改为静态ip时，网卡重启失败。想把配置文件改回去，直接copy了另一台虚拟机的ipcfg-ens33 文件，导致启动一直报错：

un 30 22:10:46 mtx network[4346]: Bringing up loopback interface:  [  OK  ] Jun 30 22:10:46 mtx /etc/sysconfig/network-scripts/ifup-eth[4482]: Device ens33 does not seem to be present, delaying initialization. Jun 30 22:10:46 mtx network[4346]: Bringing up interface ens33:  ERROR     : [/etc/sysconfig/network-scripts/ifup-eth] Device ens33 does not seem to be present, delaying initialization. Jun 30 22:10:46 mtx network[4346]: [FAILED] Jun 30 22:10:46 mtx network[4346]: RTNETLINK answers: File exists Jun 30 22:10:46 mtx network[4346]: RTNETLINK answers: File exists Jun 30 22:10:46 mtx network[4346]: RTNETLINK answers: File exists Jun 30 22:10:46 mtx network[4346]: RTNETLINK answers: File exists Jun 30 22:10:46 mtx network[4346]: RTNETLINK answers: File exists Jun 30 22:10:46 mtx network[4346]: RTNETLINK answers: File exists Jun 30 22:10:46 mtx network[4346]: RTNETLINK answers: File exists Jun 30 22:10:46 mtx network[4346]: RTNETLINK answers: File exists Jun 30 22:10:46 mtx network[4346]: RTNETLINK answers: File exists Jun 30 22:10:46 mtx systemd[1]: network.service: control process exited, code=exited status=1 Jun 30 22:10:46 mtx systemd[1]: Failed to start LSB: Bring up/down networking.  

搜了很多资料，都不适用。偶然间看到了说UUID的问题，猜测可能是uuid不对。

所以重新生成了UUID,并把它放进ipcfg-ens33配置文件中。

uuidgen ens33

vi /etc/sysconfig/network-scripts/ifcfg-ens33

修改完成后重新启动network服务，又报错了。不过这次的错误变了，看到了希望。 

Jun 30 22:51:11 mtx NetworkManager[4520]:  [1688179871.9273] ifcfg-rh: new connection /etc/sysconfig/network-scripts/ifcfg-ens33 (c96bc909-188e-ec64-3a96-6a90982b08ad,"ens33") Jun 30 22:51:11 mtx NetworkManager[4520]:  [1688179871.9279] ifcfg-rh: remove /etc/sysconfig/network-scripts/ifcfg-ens33 (fc3d45b5-3f52-4378-a334-1be1ca065345,"ens33") Jun 30 22:51:12 mtx network[4580]: Bringing up loopback interface:  [  OK  ] Jun 30 22:51:12 mtx NetworkManager[4520]:  [1688179872.2735] agent-manager: req[0x5628156cc710, :1.188/nmcli-connect/0]: agent registered Jun 30 22:51:12 mtx NetworkManager[4520]:  [1688179872.2758] audit: op="connection-activate" uuid="c96bc909-188e-ec64-3a96-6a90982b08ad" name="ens33" result="fail" reason="No suitable device found for t Jun 30 22:51:12 mtx network[4580]: Bringing up interface ens33:  Error: Connection activation failed: No suitable device found for this connection (device ens34 not available because profile is not compatible  Jun 30 22:51:12 mtx network[4580]: [FAILED] Jun 30 22:51:12 mtx network[4580]: RTNETLINK answers: File exists Jun 30 22:51:12 mtx network[4580]: RTNETLINK answers: File exists Jun 30 22:51:12 mtx network[4580]: RTNETLINK answers: File exists Jun 30 22:51:12 mtx network[4580]: RTNETLINK answers: File exists Jun 30 22:51:12 mtx network[4580]: RTNETLINK answers: File exists Jun 30 22:51:12 mtx network[4580]: RTNETLINK answers: File exists Jun 30 22:51:12 mtx network[4580]: RTNETLINK answers: File exists Jun 30 22:51:12 mtx network[4580]: RTNETLINK answers: File exists Jun 30 22:51:12 mtx network[4580]: RTNETLINK answers: File exists Jun 30 22:51:12 mtx systemd[1]: network.service: control process exited, code=exited status=1 Jun 30 22:51:12 mtx systemd[1]: Failed to start LSB: Bring up/down networking.  

 设备ens34 不可用，因为配置文件不兼容。猜测大概是修改了uuid导致的。所以把之前ens33 的配置文件改成了ens34，把文件里面的ens33 也改成ens34。

mv ifcfg-ens33 ifcfg-ens34

vi ifcfg-ens34

 TYPE=Ethernet PROXY_METHOD=none BROWSER_ONLY=no BOOTPROTO=dhcp DEFROUTE=yes IPV4_FAILURE_FATAL=no IPV6INIT=yes IPV6_AUTOCONF=yes IPV6_DEFROUTE=yes IPV6_FAILURE_FATAL=no IPV6_ADDR_GEN_MODE=stable-privacy NAME=ens34 UUID=16fcce58-c3a9-4830-857b-3538c8bd88fb DEVICE=ens34 ONBOOT=yes

重新启动网卡，没有报错了，成功！！！

 systemctl start network