A misfortune met me lately that I couldn't log in the workstation installed CentOS 7 system after I updated it. Unfortunately, I couldn't recovery it and a urgent task asked me to use the workstation to work out some result at the moment. What can I do is just to re-deploy CentOS in this workstation again and to make up mine mind to prohibit updating the operating system. And I have found this infomation can help me to achieve this aim.
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