su: Authentication failure
zonglin@zonglin-virtual-machine:~/Desktop$ su
Password:
su: Authentication failure
zonglin@zonglin-virtual-machine:~/Desktop$ sudo passwd root
New password:
BAD PASSWORD: The password is shorter than 8 characters
Retype new password:
passwd: password updated successfully
zonglin@zonglin-virtual-machine:~/Desktop$ su root
Password:
su: Authentication failure
zonglin@zonglin-virtual-machine:~/Desktop$ su
Password:
root@zonglin-virtual-machine:/home/zonglin/Desktop# ls
root@zonglin-virtual-machine:/home/zonglin/Desktop#
root@zonglin-virtual-machine:/home/zonglin/Desktop#
root@zonglin-virtual-machine:/home/zonglin/Desktop#
使用passwd修改密码
sudo passwd root # 修改root 密码
使用 su 切换用户
参考资料：