[ClusterLabs] Antw: Placing resource based on least load on a node

Michael Schwartzkopff ms at sys4.de
Tue Nov 20 02:42:18 EST 2018

Am 20.11.18 um 08:35 schrieb Bernd:
> Am 2018-11-20 08:06, schrieb Ulrich Windl:
>>>>> Bernd <bernd at kroenchenstadt.de> schrieb am 20.11.2018 um 07:21 in
>>>>> Nachricht
>> <dbae607c63168d4e14584abfba0b4b1b at kroenchenstadt.de>:
>>> Hi,
>>> I'd like to run a certain bunch of cronjobs from time to time on the
>>> cluster node (four node cluster) that has the lowest load of all four
>>> nodes.
>>> The parameters wanted for this system yet to build are
>>> * automatic placement on one of the four nodes (i.e., that with the
>>> lowest load)
>>> * in case a node fails, automatically removed from the cluster
>>> * it must only exist a single entity of the cronjob entity running
>>> so this really screams for pacemakter being used as foundation.
>>> However, I'm not sure how to implement the "put onto node with least
>>> load" part. I was thinking to use Node Attributes for that, but I
>>> didn't
>>> find any solution "out of the box" for this. Furthermore, as load is a
>>> highly volatile value, how can one make sure that all cronjobs are run
>>> to the end without being moved to a node that possibly meanwhile got a
>>> lower load than the one executing the jobs?
>> Hi!
>> Actually I think the last one is the easiest (assuming the cron jobs
>> do not need any resources that are moved): Once a cron job is started,
>> it will run until it ends, whether it's crontab has been moved or not.
>> Despite of that I think cluster software is not ideal when you
>> actually need load-balancing software.
>> Regards,
>> Ulrich
> The only resource(s) existing would be the cron "runner".
> The point about load balancing is true, yes... so, any idea what to
> use instead? Is there already a tool or framework for solving a
> problem like this available or do I have to start from scratch? Not
> that I'd be too lazy, but what's the use of reinventing the wheel
> repeatedly...? ;)
> Regards,
> Bernd
> _______________________________________________
> Users mailing list: Users at clusterlabs.org
> https://lists.clusterlabs.org/mailman/listinfo/users
> Project Home: http://www.clusterlabs.org
> Getting started: http://www.clusterlabs.org/doc/Cluster_from_Scratch.pdf
> Bugs: http://bugs.clusterlabs.org



Mit freundlichen Grüßen,


[*] sys4 AG
https://sys4.de, +49 (89) 30 90 46 64
Schleißheimer Straße 26/MG,80333 München
Sitz der Gesellschaft: München, Amtsgericht München: HRB 199263
Vorstand: Patrick Ben Koetter, Marc Schiffbauer, Wolfgang Stief
Aufsichtsratsvorsitzender: Florian Kirstein

-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 213 bytes
Desc: OpenPGP digital signature
URL: <https://lists.clusterlabs.org/pipermail/users/attachments/20181120/15a71087/attachment-0002.sig>

More information about the Users mailing list