Bug#774233: systemd shell
Control: tags -1 patch
On 2014-12-30 17:10, Antoine Beaupré wrote:
> And actually, maybe it should be a subsection like 22.214.171.124 that would be
> refered to by 5.5...
Thanks for reporting this.
The attached patch attempts to cover a basic 126.96.36.199 section for
describing how to obtain a shell under systemd if booting fails.
Admittedly, it lacks a reference from 5.5, but that should be fairly
trivial once the contents of 188.8.131.52 is in place.
A review would be greatly appreciated.
diff --git a/en/upgrading.dbk b/en/upgrading.dbk
index 4bbc849..394b60f 100644
@@ -189,7 +189,32 @@ course you will also need to fix the underlying problem and regenerate the
initrd so the next boot won't fail again.
+ <title>Debug shell during boot using systemd</title>
+ In case the boot fails under systemd, it is possible to obtain a
+ debug root shell by changing the kernel command line. If the
+ basic boot succeeds, but some of the services fails to start, it
+ may be useful to add <literal>systemd.unit=rescue.target</literal>
+ to the kernel parameters.
+ Otherwise, the kernel parameter
+ <literal>systemd.unit=emergency.target</literal> will provide you
+ with an root shell at the earliest possible point. However, this
+ is done before mounting the root file system with read-write
+ permissions. You will have to do that manually with:
+mount -o remount,rw /
+ For more information on debugging a broken boot under systemd
+ can be found in the <ulink
+ Diagnosing Boot Problems</ulink> article.