方法一:
(1)启动时任意键暂停启动
(2)按e键进入编辑模式
(3)将光标移动linux16开始的行,添加内核参数init=/sysboot/bin/sh
(4)按ctrl-x启动
(5)mount -o remount,rw /sysroot
(6)chroot /sysroot
(7)passwd root
(8)touch /.autorelabel
(9)exit
(10)reboot
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转:https://blog.51cto.com/renxi/2338391