[gpfsug-discuss] DSS-G100 and networking

[Ott Oopkaup]

Isn't this configurable during time of purchase? Our DSS-G251 and 260 
run 2x 2slot VPI cards configured to 2x ethernet in LACP bond and 2x IB. 
Basically configured for redundancy (we can lose a whole card), although 
we have maxed throughput over single port speeds.

Other thing that comes to mind is that single slot cards can effectively 
use 100% of the PCI-E link while 2 port cards might need to compromise. 
This is now again a configuration question and dependent on the ratio of 
ethernet and IB traffic.

Best,

Ott Oopkaup
University of Tartu, High Performance Computing Centre
Systems Administrator

On 7/30/25 6:41 PM, Jonathan Buzzard wrote:
>
> So these servers (at least in their SR630 V2 variant) come with three 
> single port ConnectX-6 Dx cards capable of 200Gbps.
>
> The question is why do I need three? My thinking is that a LACP bond 
> into a couple of switches doing MLAG (or insert whatever your vendor 
> calls it) is ample connectivity? Noting that these are going into a 
> pair of SN3700M switches at the full 200Gbps.
>
> So I don't get the purpose of the third card? What am I missing? Extra 
> connectivity if you want to do Infiniband as well? Direct link between 
> two of them?
>
>
> JAB.
>