No Link with DAC between WISP Switch and Routerboard

[earl]

Let me first say that I have solved my own problem with about 30 minutes of web searches only to find a Reddit post that pointed me in the right direction, so I am only posting this here for those who come along in the future with the same issue.

I could not get a link between my WISP Switch and my Mikrotik CCR Routerboard with a copper SFP DAC (Direct Attach Cable) in the SFP+ port of the Routerboard. Both devices recognized the SFP DAC and showed it in the port information, but would show the link as down. The link worked fine between the WISP Switch and the CCR only if my DAC was plugged into the CCR's SFP port (and not the SFP+ port). I discovered that to get the WISP Switch to link to a Routerboard's SFP+ port with a copper DAC you need to turn off auto negotiation on both the CCR and the WISP Switch and manually set the link speed to 1 Gbps.

I'm not sure if this is a RouterOS issue or a WISP Switch issue, but they will only link if both devices' configurations are changed. Also, this behavior was the same with a Mikrotik branded copper DAC and a Ubiquiti branded copper DAC.

I hope this helps someone else in the future and can save them some time and headache.

Thank you!

P.S. I'm enjoying my purchase of the WS-12-DC so far, have ordered about half a dozen units to trial at some sites, and look forward to using more elsewhere in the future for my WISP.