[slurm-users] Topology configuration questions:

[Prentice Bisbal]

 From https://slurm.schedmd.com/topology.html:

> Note that compute nodes on switches that lack a common parent switch 
> can be used, but no job will span leaf switches without a common 
> parent (unless the TopologyParam=TopoOptional option is used). For 
> example, it is legal to remove the line "SwitchName=s4 
> Switches=s[0-3]" from the above topology.conf file. In that case, no 
> job will span more than four compute nodes on any single leaf switch. 
> This configuration can be useful if one wants to schedule multiple 
> phyisical clusters as a single logical cluster under the control of a 
> single slurmctld daemon.

My current environment falls into the category of multiple physical 
clusters being treated as a single logical cluster under the control of 
a single slurmctld daemon. At least, that's my goal.

In my environment, I have 2 "clusters" connected by their own separate 
IB fabrics, and one "cluster" connected with 10 GbE. I have a fourth 
cluster connected with only 1GbE. For this 4th cluster, we don't want 
jobs to span nodes, due to the slow performance of 1 GbE. (This cluster 
is intended for serial and low-core count parallel jobs) If I just leave 
those nodes out of the topology.conf file, will that have the desired 
affect of not allocating multi-node jobs to those nodes, or will it 
result in an error of some sort?

-- 
Prentice