[systemd-devel] Q on serial-getty

[Silvio Knizek]

Am Mittwoch, den 07.10.2020, 08:49 +0200 schrieb Ulrich Windl:
> Hi!
>
> I'm thinking of configuring a serial getty in SLES15 (systemd-234). First I found that there is no manual page describing the service, and second if I use "systemctl show serial-getty" ("systemctl show serial-getty@" does not work), I get some "funny" numbers:
>
> ...
> UID=4294967295
> GID=4294967295
> ...
> MemoryCurrent=18446744073709551615
> CPUUsageNSec=18446744073709551615
> TasksCurrent=18446744073709551615
> IPIngressBytes=18446744073709551615
> IPIngressPackets=18446744073709551615
> IPEgressBytes=18446744073709551615
> IPEgressPackets=18446744073709551615
> ...
> CPUWeight=18446744073709551615
> StartupCPUWeight=18446744073709551615
> CPUShares=18446744073709551615
> StartupCPUShares=18446744073709551615
> ...
>
> Obviously that number is the unsigned 64-bit representation of -1, but considering that no such service is running, the output looks quite odd.
> If -1 means "unknown", why not use that string, or if it means "unlimited", why not use that string?
>
> Regards,
> Ulrich

Hi Ulrich,

have you already tried `systemctl help serial-getty at foo.service` (yes,
instanciatable units need a instance token, even if useless)? This
should open some documentation.
Also, for the serial getty actually a generator is used to
automatically start it, if already requested by the boot loader and
kernel command line. See man:systemd-getty-generator(8) and
http://0pointer.de/blog/projects/serial-console.html for more
information.

BR
Silvio