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I'm trying to boot into emergency mode but i'm having no joy.
I can boot to single user mode (by adding s or single at the end of the kernel line in grub) and I can also boot to init=/bin/sh mode by using the same method, but emergency is not working.
Any ideas?
I'm using RHEL6 x64
I don't actually have a real problem, I'm just running through some training.
1.
At the GRUB splash screen at boot time, press any key to enter the GRUB interactive menu.
2.
Select Red Hat Enterprise Linux with the version of the kernel that you wish to boot and type a to append the line.
3.
Go to the end of the line and type single as a separate word (press the Spacebar and then type emergency). Press Enter to exit edit mode.
If I append single or s, it boots in single user mode
If I append init=/bin/sh, it boots in bin/sh mode (not sure what it is called)
if I append emergency, RHEL boots up normally.
Rhel6 emergency mode is still a thing. while the init=/bin/bash access method is very much the same, the emergency kernel argument is fully operational. in RHEL6.1 there was a bug that broke that functionality, but in rhel 6.2 and above, it's back up and functioning. Also remember that you can init into any shell loaded on the system in the event that bash is broken or lost.
"In emergency mode, you are booted into the most minimal environment possible. The root file system is mounted read-only and almost nothing is set up. The main advantage of emergency mode over single-user mode is that the init files are not loaded. If init is corrupted or not working, you can still mount file systems to recover data that could be lost during a re-installation.
To boot into emergency mode, use the same method as described for single-user mode in Section 36.1.3, “Booting into Single-User Mode” with one exception, replace the keyword single with the keyword emergency."
In RHEL v6, this can be achieved by booting in from RHEL install DVD
Boot from RHEL install DVD
Select 'Rescue Installed System'
Select 'Local CD/DVD'
Select 'Network interface'# exit
Select read only or read write
Start shell
At this point, either you can mount any partition/filesystem for backup, or you can change root(/) by giving chroot command
Just realized the post is more than 2 years old...
I only posted because the information above is wrong lol. And technically what you're suggesting is Rescue Mode. To reach Emergency Mode without using the Anaconda installer via an installation media (disk, iso, PXE boot) you can just add the kernel argument "emergency" in RHEL 6.2 or higher, or any version of RHEL5 or below. There was a bug that broke that functionality in 6.0 and 6.1. In those versions, it would be necessary to add the kernel argument init=/bin/bash (or any other shell installed on the system such as CSH [which comes packaged on most RHEL systems], KSH or ZSH).
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