Can SFP and QSFP ports be used simultaneously? Specs seem to say no...

[timbaker]

Hello Meraki Community,

According to specs listed here: https://meraki.cisco.com/product/switches/stackable-access-switches/ms355-24x/

...the MS355 can use 2 × 40G OR 4 × 10G fiber uplinks.  

Does this really mean that it is not possible to use the QSFP and SFP ports simultaneously?

Thanks!

Tim.

[cmr]

@timbaker I saw that too, but they are separate in the dashboard (ports 49-52 being SFP+ and 53-54 being QSFP+) so I'd have thought that is not the case.  I can confirm that the QSFP+ ports work but I haven't yet tried to use both port types at once.

[timbaker]

Thanks @cmr - that is encouraging...

Has anyone out there used SFP and QSFP simultaneously on an MS355?  Or can a Meraki rep confirm the meaning of the statement in doco?

[cmr]

@timbaker I think it may be one or the other, if you add (32x1+16x10+4x10+2x40)x2 you get 624 whereas if you lose the (4x10)x2 by only using the QSFP+ ports and not the SFP+ ports, you get 544 which is the published switching bandwidth.

I must say, I did not notice if any of the SFP+ ports were disabled when I used the QSFP+ ports and am not planning to be at that site for a few weeks so cannot test again for now.  If the ports are an or, I would guess that each QSFP+ port will disable the two SFP+ ports on the same row.

[timbaker]

Nice work, @cmr - that is interesting indeed.

Has anyone out there put this to the test?  

Or can someone from Meraki provide clarification?

Thanks

[Phi-L]

This should work. The MS355 should not care whether or not both QSFP+ and SFP+ uplink types are being used simultaneously and should be able to function even if the maximum available ports are in use.

[timbaker]

@Phi-L Thanks for this.  However, you said it "should" work whereas I really need to know whether it will or not...  Are you able to provide a definitive answer from Meraki?  ie: is it a viable and supported configuration to use all QSFP and SFP ports simultaneously on an MS355?

[timbaker]

Does anyone out there have a definitive answer to this?  @Phi-L, is this info something you can source internally with Meraki?   

(I'm working on a fibre upgrade project with 50+ Meraki switches and need to know how many QSFP/SFP ports are actually useable)

Thanks...

[timbaker · Accepted solution]

For anyone out there interested in this topic, I got the following from Meraki support:

"Both SFP and QSFP ports can be used simultaneously for different purposes."

and

"The ports themselves are independent of each other and using one type does not disable the other type."