Debian username and password IP addresses are all forgotten

Solve the problem that all the IP addresses of Debian user names and passwords are forgotten-Debian information of the Linux release-the following is a detailed description. I haven't used this server for a long time. Today, a colleague suddenly asked me to use it and forgot everything. This is a headache. There are a lot of online materials.

The following describes how to use grub in all linux Versions:

1. On the Grub boot loader menu, select the entry you want to enter and type "e" to enter the editing mode.
2. In the second line (similar to kernel/boot/vmlinuz-2.6.15 ro root =/dev/hda2), Type e to enter edit mode;
3. Add "init =/bin/bash" at the end of the sentence and press Enter;
4. Press "B" to start the system.
In this way, we can get a bash shell.

View
Username: # cd/etc
# Cat hostname
IP:/etc/network/interfaces

Then change the password:
After entering the shell, the Mount mode of the root partition is read-only by default. We need to change it to writable; otherwise, the root password cannot be changed:

Mount-no remount, rw/
Passwd root
Sync
Mount-no remount, ro/
Reboot