UDLD neighbor mismatch errors connecting City Wide Locations over point to multipoint wireless

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UDLD neighbor mismatch errors connecting City Wide Locations over point to multipoint wireless

I have built a City Wide RadWin point to multi point wireless network to connect our facilities and equipment back to City Hall.

Our Water Tanks are the central locations for each sector and connect to the Phillips Building then fiber to City Hall.


We receive UDLD neighbor mismatch errors all the time on any switch that is connected to the same wireless sector radio.


Example Fire Station 2 MS120 Switch and Frontier Pool MS120 Switch each with a RadWin SU point to the same RadWin AU on top of the Phillips Building connected to a MS120 Switch then fiber down to City Hall connected to a MS425


Has anyone else built out a wireless point to multi point network using Meraki MS switches at multiple locations?

Below is an overview of the build out with a future loop if I can get the UDLD errors taken care of.



3 Replies 3
Kind of a big deal
Kind of a big deal

UDLD is typically used between switch links to prevent unidirectional communication, causing the spanning tree to erroneously place a discard port on the designated forwarding due to non-receipt of BPDUs. This error state generally only exists if one fiber in the pair no longer transmits due to an optical or cable error.



I am not a Cisco Meraki employee. My suggestions are based on documentation of Meraki best practices and day-to-day experience.

Please, if this post was useful, leave your kudos and mark it as solved.

The links are all coper to wireless subscriber units that passes all traffic. act as a transparent bridge.

So UDLD and BPDU are all flowing.

Problem is UDLD is seeing both Switches on the same port and thinking its a loop when its not.

As in the Docs from end to end UDLD is supported.

I suspect the multipoint technology being used is not properly handling the UDLD packets.  I would just disable UDLD.

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