MRTG

My network was EIGRP with Cisco routers. We switched to a bridged network while we replaced the Ciscos with Mikrotiks. Then we changed to OSPF. After the OSPF change we can no longer graph any data with our MRTG server. Any ideas why?

I think you’re looking at the wrong issue here. Whether you run OSPF or EIGRP has nothing to do with graphing.
Graphing comes through SNMP. Check if you’re graphing the right OIDs, as the MIBs may be different between cisco and MikroTik.

Sorry I did not give you all the info. We are a WISP. The MRTG is for the Canopy Radios. So after the OSPF change the MRTG stopped talking to the Canopy radios. Is there a setting in the MIkrotiks that I missed to allow SNMP traffic through?

by default there are no limitations for any kind of traffic to start with. Check if router is reachable. Check if you can access SNMP information from host manually (like snmpget or something) check your end equipment if it accepts connections from other networks (since network is routed now)