After hours of debugging, I got this 20MHz single-polarity link moving up to 55Mbit. A high resolution spectrum analysis on both sides did indeed show a better frequency to use for the link. Spectrum analysis captures here: https://imgur.com/a/4H7GB There was also an IP conflict between two modems @ Capitol Park. The conflicting IP has been removed from CapitolPark-S3. The QueenAnne modem used for the link is not one used anywhere else on the network. It's a very low-end modem, and as a result it was having CPU/RAM starvation issues when running our regular diagnostic tools, which lead to out-of-memory conditions and kernel crashes. A different test methodology had to be used to verify the link speed (testing through the modem, instead of to the modem). The modem that links QueenAnne with the Westin building (on the QueenAnne side) had a mis-configured OSPF router-id. This was fixed. I'm still seeing weird routing decisions being made by OSPF. These are triggered by our point-to-point route entries (44.24.242.0/24 space). More research needs to be done here, and perhaps a re-write of how we define point-to-point interface addresses. Any OSPF experts in the house? I also discovered R1.QueenAnne was still vulnerable to hacking due to a mis-configuration of its control software. It missed the updates that were sent out to the whole network. This has been fixed now. R1.QueenAnne also didn't have the diagnostic bandwidth-server setup correctly. This was fixed. With the CapitolPark-QueenAnne link performing well now: [eo@CapitolPark-QueenAnne] /system resource> /tool bandwidth-test 44.24.241.81 direction=both status: running duration: 57s tx-current: 28.0Mbps tx-10-second-average: 28.4Mbps tx-total-average: 27.5Mbps rx-current: 27.6Mbps rx-10-second-average: 28.0Mbps rx-total-average: 27.0Mbps lost-packets: 288 random-data: no direction: both tx-size: 1500 rx-size: 1500 its OSPF config has been reset to a normal preference level, so that packets no longer try to avoid that link as they are routed through the network. This link can be sped up by upgrading to a dual-polarity modem @ CapitolPark. While testing if the OSPF hop cost was being calculated correctly in the Beacon-Haystack-QueenAnne RF link (they both connect to the same dish @ Haystack), I discovered a mis-config on the Haystack.Beacon modem (bad LAN IP binding) which was preventing it from bringing up OSPF on its LAN interface. This was fixed and that modem should act like an actual router now, moving traffic. During the same Beacon testing, I was reminded that our Baldi-Beacon RF link sucks <https://monitoring.hamwan.net/cacti/graph.php?action=view&local_graph_id=919&rra_id=all>. It was optimized for speed to Tukwila, which is now gone, so a trip needs to be scheduled to Baldi to rotate the dish a few degrees north and get that link going strong. I normally wouldn't send this kind of verbose email to psdr@, but I hope it's illuminating as to the type and extent of work required to keep this network running well. --Bart