topic Re: QSFP+ DAC for V160 stacking in X590 switches in ExtremeSwitching (EXOS/Switch Engine)

QSFP+ DAC for V160 stacking in X590 switches

Viththahan — Sun, 25 Jul 2021 12:19:47 GMT

In the EXOS Hardware Installation Guide;

In the IRIS, the QSFP+ DAC are available from 0.5m to 5m lengths.

Won't the QSFP+ DAC work on the X590 switches for V160 stacking?

Re: QSFP+ DAC for V160 stacking in X590 switches

Stefan_K_ — Sun, 25 Jul 2021 16:29:37 GMT

Hi @viththahan

I think it’s pretty clear. Only QSFP28 possible, not QSFP+.

Best regards
Stefan

Re: QSFP+ DAC for V160 stacking in X590 switches

Viththahan — Sun, 25 Jul 2021 16:35:00 GMT

Dear Stefan,

I need to confirm this because the compatibility matrix shows this; says it’s compatible.

Re: QSFP+ DAC for V160 stacking in X590 switches

Stefan_K_ — Sun, 25 Jul 2021 16:54:05 GMT

Aah, now I understand. 😄

Well, the Stacking section in the EXOS User Guide (ExtremeXOS® User Guide Version 31.3 > Configuring Stacked Switches > Introduction to Stacking > Available Stacking Methods) also states that QSFP+ is supported:

This is only the case for EXOS 30.2 and above. For 22.6 and 22.7 QSFP+ is not listed for X590, only QSFP28.

I would conclude that QSFP+ is supported, with 30.2+.

Where exactly did you find the information (screenshot) in your initial post?

Re: QSFP+ DAC for V160 stacking in X590 switches

Viththahan — Sun, 25 Jul 2021 17:02:09 GMT

It's on the page 203 of the EXOS Hardware Installation Guide.

https://documentation.extremenetworks.com/extremeswitching/downloads/GUID-C9BE5F30-C3F1-4840-AAE3-AEA3C21A4949.pdf

So now it's confirmed. Great thanks!

Re: QSFP+ DAC for V160 stacking in X590 switches

Stefan_K_ — Sun, 25 Jul 2021 17:27:12 GMT

On Page 189 of the same document QSFP+ is listed for X590. The information on page 203 might be a mistake, same goes for X690 (page 206).

Well, nobody likes contradictory statements in official documentations, maybe @Christopher Thompson or @Sam Pirok can give a final answer and get this fixed.

Re: QSFP+ DAC for V160 stacking in X590 switches

BrandonC — Tue, 27 Jul 2021 02:45:45 GMT

Starting in EXOS 30.2, support for V160 stacking was added for the X590 and X690. This uses QSFP+ cables and compatibility with more EXOS switches (at the downside of lower stack backplane bandwidth).

Before this, only V400 stacking was supported on the X590 and X690, which required QSFP28 cables for the additional bandwidth.

It looks like that top disclaimer in the hardware installation guide didn’t get updated when this change went in to effect. I’ll reach out to the documentation team so we can get this updated.

Re: QSFP+ DAC for V160 stacking in X590 switches

Stefan_K_ — Tue, 27 Jul 2021 14:28:48 GMT

Hi Brandon,

thanks for clarification! 🙂

Re: QSFP+ DAC for V160 stacking in X590 switches

jeronimo — Wed, 24 Aug 2022 13:29:12 GMT

Sorry for being late to the party but there are still some things not clear. See below screenshot

So which is the case, QSFP+ supported or not? Probably they also mean 40m and not 40Km. 😉

UPDATE Oups I see this is X690 as opposed to X590 in this thread. Hope you forgive me. I think I'll just reach out to TAC to obtain the information and get the docs fixed.