---
title: Automatic Boot Assessment
+category: Booting
+layout: default
---
# Automatic Boot Assessment
script can optionally create boot loader entries that carry an initial boot
counter (the initial counter is configurable in `/etc/kernel/tries`).
-# Details
+## Details
The boot counting data `systemd-boot` and `systemd-bless-boot.service`
manage is stored in the name of the boot loader entries. If a boot loader entry
see the `+1-2` tag, and rename the file to
`4.14.11-300.fc27.x86_64+0-3.conf` and boot it.
-6. If this boot also fails, on the next boot the boot loader will see the the
+6. If this boot also fails, on the next boot the boot loader will see the
tag `+0-3`, i.e. the counter reached zero. At this point the entry will be
considered "bad", and ordered to the end of the list of entries. The next
newest boot entry is now tried, i.e. the system automatically reverted back
12. On the following boot (and all subsequent boots after that) the entry is
now seen with boot counting turned off, no further renaming takes place.
-# How to adapt this scheme to other setups
+## How to adapt this scheme to other setups
Of the stack described above many components may be replaced or augmented. Here
are a couple of recommendations.
wrap them in a unit and order them after `boot-complete.target`, pulling it
in.
-# FAQ
+## FAQ
1. *Why do you use file renames to store the counter? Why not a regular file?*
— Mainly two reasons: it's relatively likely that renames can be implemented