> On Jan 23, 2020, at 11:09 AM, Derek Dagit <da...@apache.org> wrote:
>
> +1 for concept and rationale
>
> Might be good to survey the common log rotation tools to verify custom
> signals are supported.
>
> On Thu, Jan 23, 2020 at 11:16:25AM -0600, Brian Neradt wrote:
>>
>> Context
>> ======
>>
>> Traffic Server currently implements its own mechanism for rotating its logs
>> and cleaning up (i.e., deleting) rotated logs based upon configured
>> constraints. These features seem to have been developed at a time when
>> third party tools for managing such logs were non-existent or immature.
>> Today administrators have tools such as logrotate they can use to manage
>> logs. Such tools handle log rotation and deletion (and compression,
>> automated emailing, and other related features) in a way that
>> administrators are generally familiar with and would prefer to use for
>> consistency across their log management needs. After rotating their logs,
>> these tools send a signal to the process generating the logs so they can
>> close and re-open the logs. Traffic Server does not currently support
>> external log managers because it does not support listening for such
>> signals.
>>
>> Proposal
>> =======
>>
>> In order to support the use of tools such as logrotate, this proposal
>> suggests adding support for Traffic Manager and Traffic Server to handle a
>> signal that causes those processes to close and re-open their logs handles.
>>
>> Further, while SIGHUP is a pretty common signal used for such purposes,
>> this proposes SIGUSR2 instead since we already use that for traffic.out
>> (added via https://github.com/apache/trafficserver/pull/274/files).
Also, for this change, it’d be fine to rearrange which signal is used for what.
SIGHUP is by far the most common way to do log rotation, and it’d be unorthodox
to not use it IMO. We can move our existing usage of HUP over to e.g. USR1/2
etc.
Cheers,
— leif
>>
>>
>> Please share any thoughts or suggestions.
>>
>> Thanks,
>> Brian
>> --
>> "Come to Me, all who are weary and heavy-laden, and I will
>> give you rest. Take My yoke upon you and learn from Me, for
>> I am gentle and humble in heart, and you will find rest for
>> your souls. For My yoke is easy and My burden is light."
>>
>> ~ Matthew 11:28-30
