Is it possible to mix stacking method when I stack 5520 with 5420 series switches?

[RobertoV]

Is it possible to mix stacking method when I stack 2 switches 5520 (without VIM-4X) and 2 switches 5420 series switches using U1 and U2 port , using QSFT+ to QSFP+ cable between 5520 (SummitStack-V160) and special cable which converts QSFP+ to SFP-DD cable between 5520 and 5420 (SummitStack-V80)?

https://documentation.extremenetworks.com/wired/5520/GUID-E6A46A78-F511-45C4-AD7B-5206FE865992.shtml

If it is possible do I have to write a special configuration in the Stacked Switches?

Thanks

[Gabriel_G · Accepted solution]

As the document states, yes, it is possible.

You will need to set the appropriate stacking-support setting for each stack port.

configure stacking-support stack-port <stack-port> selection [native [V40 | V80 | V160 | V200 | V320 | V400] | alternate]

v80 for 20G

v160 for 40G

The special cable appears to be:

20G-DACP-QSFP1SFPDD1M - QSFP to SFP-DD, 20G, 1M

20G-DACP-QSFP1SFPDD3M - QSFP to SFP-DD, 20G, 3M

20G-DACP-QSFP1SFPDD5M - QSFP to SFP-DD, 20G, 5M