[Buildroot] log storage strategy

[Arnout Vandecappelle <arnout@mind.be>]

On 05/03/15 10:30, Sylvain LG wrote:
> Hello,
> 
> many services like to write log files.
> 
> I suppose that it could be a problem on an embedded device, since space is
> limited and NAND has write limitation in time.
> 
> What is the correct strategy to deal with log?

 There is no single strategy that will work for everybody.

 Often the logs are put in a tmpfs so they are never committed to NAND. But then
of course you loose them when the system reboots.

 If you do write to flash, with a decent wear-levelling filesystem the write
limit is not necessarily a problem, especially if you enable some write
buffering (which defaults to 5-30 secs anyway, cfr. sysctl
vm.dirty_writeback_centisecs and vm.dirty_expire_centisecs) and rate limiting
(rsyslogd and journald have controls for that).

 And finally, you'll have to clean up old logs. You can use logrotate, or the
built-in rotation in rsyslogd and journald.


 Regards,
 Arnout
-- 
Arnout Vandecappelle                          arnout at mind be
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