[slurm-users] Several slurmdbds against one mysql server?

[Ole Holm Nielsen]

On 5/1/23 09:22, Angel de Vicente wrote:
> This is the first time that I'm installing Slurm, so things are not very
> clear to me yet (even more so for multi-cluster operation).
> 
> Brian Andrus <toomuchit at gmail.com> writes:
> 
>> You can do it however you like. You asked if there was a good or existing way to
>> do it easily, that was provided. Up to you if you want to write your own scripts
>> that do the work and manage that, or just have to learn the ins and outs of
>> running sreport.
> 
> I'm not sure what scripts you have in mind above, since as far as I can
> see I already have a working solution for what I need (i.e. keep all job
> records from different clusters in a single database).

If I read Brian's comments correctly, he's saying that Slurm already has a 
well-tested and documented solution for multi-cluster sites: Federated 
clusters.  You don't HAVE to use the solution that Slurm/SchedMD provides, 
but it will be the easy and well tested solution for you.

If you don't want to use federated clusters, you are free to do so.  But 
then you have to write *your own scripts* to implement your own ideas. 
Probably no-one can help you with your ideas, and you will have to develop 
everything by yourself from scratch (not an easy task if this is your 
first experience with Slurm).

I hope Brian's comments will help you select the best way forward.  The 
slurm-users list is generally helpful, also to new Slurm users.

/Ole


> But let's say I go for the federated cluster option. I think my question
> still holds. Let's say, for clarity, that I have two clusters (CA and
> CB) and another machine (DB) where I will store the mysql database. As
> far as I can see, in terms of the daemons running in each machine, I can
> implement the whole thing in two ways:
> 
> option 1)
>    CA: slurmd, slurmctld (AccountingStorageHost: DB)
>    CB: slurmd, slurmctld (AccountingStorageHost: DB)
>    DB: slurmdbd, mysqld
> 
> option 2)
>    CA: slurmd, slurmctld, slurmdbd (StorageHost: DB)
>    CB: slurmd, slurmctld, slurmdbd (StorageHost: DB)
>    DB: mysqld
> 
> 
> By reading the documentation on multi-cluster and federated clusters I
> think option 1) is the preferred way, but I was just trying to
> understand why and what are the pros/cons of each option.