Booting in rescue mode on CentOS 7
Systems upgraded from versions before 11.3 running CentOS6
Appliances deployed using versions older than 11.3 and subsequently upgraded to 11.3 still use CentOS 6. Refer to Changing the grub password the 11.2 documentation.
On CentOS7 systems, the rescue boot option loads the rescue kernel but then starts all services, including the Discovery services. If you need to boot in a single user mode with only essential system services running, you must specify a rescue target for systemd.
- The grub user is: root
- The default grub password is: B00tl0ad3r!
To specify a rescue target for systemd:
- At the GRUB boot screen press e to modify the boot options.
- Enter the grub user when prompted
- Enter the grub password when prompted.
- Scroll to the
linux16entry and add the following parameter at the end of the line:
- Press Ctrl+X to boot the system into rescue mode.
To change the grub password
You must be the root user to change the grub password.
# grub2-mkpasswd-pbkdf2You are prompted to enter the password
- Then edit
/boot/grub2/user.cfgand replace the value after: