MX250 WAN 1 & 2 stuck at 1Gbps (Won't pick up 10Gbps)

[Willrockhopper]

We have have two MX250's in a high availability config in our primary data rack, and have just upgraded the WAN 1 & 2 links on these to use 10Gbps fibre (previously running 1Gbps RJ45).

The secondary MX had no issues with this, and reports on the dashboard that both links are operating at full duplex 10Gbps.

However, the primary unit has an issue which is causing it to stay at 1Gbps, despite now having 10 gig capable SFP's inserted with the same in the C9300 it is connected to. The catalyst switch at the other end also reports that the links to the primary MX are operating at reduced speed, as it recognises the links should be running at 10 gig opposed to 1.

If anyone can offer some suggestions on how to resolve this that would be awesome. We've already tried a reboot to no avail.

Cheers

[alemabrahao]

I suggest you open a support case.

[RWelch]

What happens if you were to swap the known good SFP and fiber patch cable?  Does the primary then function as expected?  Just trying to rule out a possible bad SFP+ transceiver and possibly fiber patch cable?  Perhaps you have already given this a try?

And the obvious one - make sure both ends are indeed SFP+ transceivers (if I understand your situation correctly).

[RWelch · Accepted solution]

Might also be worth logging into the MX directly (local status page) to verify the port type is set to auto vs manually set for Ethernet or SFP/SFP+) and negotiation speed are set to auto (Meraki's preferred setting) and you could always set to force (set speed).  Typically the link won't work if one end is SFP and the other is SFP+ or vice versa - but we all have seen or had odd things happen before.

[Willrockhopper]

Thanks for this - great suggestion!

I had tried to get into the page earlier but it wasn't working. Tried again and sure enough, both WAN interfaces had been set to 1Gbps fixed for some unknown reason. Changed to 1/10 Auto and working perfectly now.

Cheers!