F21 Self Contained Change: Remote Journal Logging

[Zbigniew Jędrzejewski-Szmek]

On Thu, Apr 17, 2014 at 07:33:16AM -0400, Martin Langhoff wrote:
> On Wed, Apr 16, 2014 at 5:08 PM, Zbigniew Jędrzejewski-Szmek
> <zbyszek at in.waw.pl> wrote:
> >> So I'll ask you about this other aspect -- what about stateless
> >> clients with very limited or no local storage?
> > Not supported by this, unfortunately. There needs to be at least
> > temporary storage in tmpfs for this scheme to work.
> 
> Can the storage space used be limited with a parameter to avoid
> ENOSPC? Can journald be told to start discarding the data (oldest or
> latest) when it reaches the limit?

Yeah, it's standard journald behaviour. By default journald will limit
both the total disk usage, and will also not fill the fs above 90% (iirc).
There were various issues with this logic in the past, but it seems to
behave fairly robustly now. The idea is
that journald does the "right thing" without any configuration or
maintenance.  The logic is suitable for normal fs layout, but if
something different is needed, especially if you have a dedicated fs
for log storage that can be filled to the brim, the limits and
thresholds are all configurable (see
http://www.freedesktop.org/software/systemd/man/journald.conf.html#SystemMaxUse=
for available options).

Zbyszek