Sometimes a config error, lost root password, broken fstab entry, or failed filesystem leaves a RHEL system stuck. The recovery toolbox covers three common scenarios: (1) lost root password → rw init=/bin/bash at the GRUB menu; (2) broken fstab mount → boot into emergency.target and edit /etc/fstab; (3) broken service preventing boot → boot into rescue.target and disable the offender. All three rely on editing the kernel command line at the GRUB menu to change the early-boot behavior for one boot.
Version watch: on RHEL 10 — your exam version —
init=/bin/bash is THE password-reset method. The classic
rd.break recipe from older reference sheets no longer gets you a usable shell on RHEL 10: the initramfs emergency shell is locked and demands the root password you don't have.
rd.break still works on RHEL 9, so learn it as the legacy path, but drill
init=/bin/bash as your exam answer.
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