systemd-debug-generator

systemd
systemd-debug-generator 8
systemd-debug-generator Generator for enabling a runtime debug shell and masking specific units at boot

`/usr/lib/systemd/system-generators/systemd-debug-generator`

## Description

`systemd-debug-generator` is a generator that reads the kernel command line and understands three options:

If the `systemd.mask=` or `rd.systemd.mask=` option is specified and followed by a unit name, this unit is masked for the runtime (i.e. for this session - from boot to shutdown), similar to the effect of systemctl 1's `mask` command. This is useful to boot with certain units removed from the initial boot transaction for debugging system startup. May be specified more than once. `rd.systemd.mask=` is honored only by initial RAM disk (initrd) while `systemd.mask=` is honored only in the main system.

If the `systemd.wants=` or `rd.systemd.wants=` option is specified and followed by a unit name, a start job for this unit is added to the initial transaction. This is useful to start one or more additional units at boot. May be specified more than once. `rd.systemd.wants=` is honored only by initial RAM disk (initrd) while `systemd.wants=` is honored only in the main system.

If the `systemd.debug_shell` or `rd.systemd.debug_shell` option is specified, the debug shell service `debug-shell.service` is pulled into the boot transaction and a debug shell will be spawned during early boot. By default, `&DEBUGTTY;` is used, but a specific tty can also be set, either with or without the `/dev/` prefix. Note that the shell may also be turned on persistently by enabling it with systemctl 1's `enable` command. `rd.systemd.debug_shell=` is honored only by initial RAM disk (initrd) while `systemd.debug_shell` is honored only in the main system.

`systemd-debug-generator` implements systemd.generator 7.

## See Also

systemd 1, systemctl 1, kernel-command-line 7