[systemd-devel] Feature suggestion: journalctrl -b <n>

[Lennart Poettering]

On Wed, 26.09.12 23:51, Henrik /KaarPoSoft (henrik at kaarposoft.dk) wrote:

> Dear all,
> 
> "journalctrl -b" shows messages from the current boot.
> 
> However, I often find it useful to look at messages from the previous boot.
> 
> Hence I would like to propose a new feature:
> "journalctrl -b <n>"
> should show messages from the n'th previous boot,
> default being n=0, i.e. current boot.
> 
> What do you think about this?

Sounds like a good idea. Added this to the TODO list.

> PS:
> It might also be useful to have an option to show all boot-ID's in
> the journal,
> maybe showing first and last timestamp of the log, and number of entries.
> And maybe having an option like "journalctrl -b <boot-ID>"

Yes, it is actually our plan to implement work-alikes for "last",
"lastlog" and suchlike to systemd that simply take the data out of the
journal for that. A similar tool could be one that inspects boot IDs
like you suggest. To make this work nicely we need a minor update of the
journal indexing logic however (which is already there in the format,
but not implemented)

Lennart

-- 
Lennart Poettering - Red Hat, Inc.