It's rare, but a failed and/or buggy update might prevent successful boot-up of the system.
Usually the best option is to try the previous (fall-back) image, but there are occasions where this also might not work (e.g. if SystemD and the Linux Kernel are incompatible).
There are a few hurdles:
- Work out what the cause of the problem is:
- Access to the command line is probably essential
- Be able to install an upgrade and/or fix:
- A connection to the internet may be required
- Access the contents of the encrypted drive
- Access the drive as an authorised user
Diagnosing the problem
There are a quite a few tools to use to figure out where errors are occurring, but in order to do this, you will need access to the command line. Remember that if the window / tiling manager is non-functional there is also the option to switch to a log-in terminal with
The tool I usually use to check logs is
journalctl -r, although there are more, depending on what you're looking for.
Accessing the contents of your hard drive
If you download the latest Manjaro ISO, and
dd if=/path/to/my-image.iso of=/dev/sdz status=progress it to an SD card or thumbdrive
sdz is replaced with the computer's USB device - you can use
lsblk -f to find this out.
Mount the drive
cryptsetup open --type luks /dev/sda1 crypto_LUKS mount /dev/mapper/crypto_LUKS /mnt
Connect as a root user
Update the system
pacman -Syu # Or install alternative kernel pamac install linux510