Twinax compatibility

[steakandeggs]

A customer wants 5m twinax cables, but the only cables Meraki sells are 1m and 3m, such as MA-CBL-TA-3M. Do the standard Cisco twinax cables work fine with Meraki switches, such as Cisco SFP-H10GB-CU5M?

[cmr]

@steakandeggs as it looks like you are using them for a device connection, as opposed to stacking, then they should be fine.  We use Dell DACs without issue.

[PhilipDAth]

I've wondered about this for quite a while.  Why does Meraki only offer up to 3m TwinAx.  Are the SFP+ ports lacking sufficient power to drive a 5m cable reliably?  Do they have some kind of timing issue?

I've changed my designs to only use the Meraki 3m cables to be safe (it would be expensive for me to get this wrong for a customer and have to pay to swap out for fibre).

If you try it out, let us know how it goes.

[GIdenJoe]

That is a great question and one would wonder if maximum power draws are in the SFP standards or if every vendor tries to keep within their own specs.

[Ryan_Miles]

I've also used Cisco branded 7M twinax between switches and switches/MXs and it's been fine. Not saying it's officially supported. Just saying what I've tried and what I experienced.

[PhilipDAth]

I'm not aware of passive 7m TwinAx cables.  Did you use active TwinAx?

[cmr]

@PhilipDAth I've not used them, but FS sell 7m DACs: https://www.fs.com/uk/products/39292.html?attribute=1325&id=222677

Their "Cisco" 10Gbase-T transceivers work well with Meraki

[PhilipDAth]

That is interesting to know!