Introduction
passwd root Exit the chroot, unmount, and reboot. Remember to remove the ISO from the virtual drive. Important Post-Recovery Considerations Resetting the password is only half the battle. You must also handle the configuration database .
chroot /mnt/sysimage Now reset the password: F5 Recover Root Password
If you booted into "single" user mode, the mcpd (Management Control Process) likely did not start. After logging in normally with your new password, run:
passwd Before rebooting, ensure the password hash is written to disk: Introduction passwd root Exit the chroot, unmount, and
While recovering a lost root password is stressful, F5’s reliance on standard Linux bootloaders makes it straightforward. before your production system locks you out on a change control Friday night. Disclaimer: The information provided is for administrative use on systems you own or have explicit permission to manage. Unauthorized password recovery attempts may violate security policies and laws.
sync reboot -f On newer BIG-IP versions (15.x+ with Full Disk Encryption) or if the GRUB menu is password-protected, the single method may fail. In these cases, use the F5 Recovery ISO . Step 1: Obtain the ISO Download the recovery ISO from F5 Downloads (search for "Recover ISO" matching your version) using your support credentials. Step 2: Boot from the ISO Mount the ISO via your hypervisor or iLO, then boot the system from it. Select "Rescue installed system" from the menu. Step 3: Mount the Root Partition The recovery environment will detect your existing installation. When prompted, select 1 to mount the root partition under /mnt/sysimage . Step 4: Chroot and Reset Change root into the mounted system: You must also handle the configuration database
Unlike typical Linux servers where you can append init=/bin/bash to the kernel boot line, F5’s proprietary TMOS (Traffic Management Operating System) requires a specific procedure using the and the boot manager . Prerequisite: This method requires physical or out-of-band (iLO/iDRAC/IPMI) console access to the device. It will not work over SSH. Method 1: The Standard Recovery (SINGLE User Mode) This is the safest method and works for BIG-IP versions 11.x through 17.x. Step 1: Access the Console & Reboot Connect via serial console. If the device is running, issue the command:
For F5 administrators, losing the root password to a BIG-IP device (whether physical appliance or virtual edition) can feel like being locked out of your own data center. Fortunately, F5 provides a well-documented, albeit physically demanding, backdoor recovery process.
mount -o remount,rw / Type passwd and enter your new root password twice: