[ClusterLabs] Antw: Re: Antw: Re: Antw: [EXT] Re: A bug? (SLES15 SP2 with "crm resource refresh")

[Ulrich Windl]

>>> Ken Gaillot <kgaillot at redhat.com> schrieb am 11.01.2021 um 16:45 in Nachricht
<3e78312a1c92cde0a1cdd82c2fed33a679f63770.camel at redhat.com>:

...
>> > from growing indefinitely). (Plus some timing issues to consider.)
>> 
>> Wouldn't a temporary local status variable do also?
>

Hi Ken,

I appreciate your comments.
 
> No, the scheduler is stateless. All information that the scheduler
> needs must be contained within the CIB.
> 
> The main advantages of that approach are (1) the scheduler can crash
> and respawn without causing any problems; (2) the DC can be changed to

I think it's nice when being able to recover smoothly after a crash, but program design should not be biased towards frequent crashes ;-)

> another node at any time without causing any problems; and (3) saved

Well, if every status update is stored in the CIB (as it seems to be), changing DCs shouln't be a bug problem until there are multiple at the same time.

> CIBs can be replayed for debugging and testing purposes with the
> identical result as a live cluster.

Are you talking about the whole CIB, or about the configuration section of the CIB? I can't see any sense of replacing the status section of the CIB unless you want to debug resource recovery and probing.

...

Regards,
Ulrich