[solved] RB750 does not work with cisco uBR900 cable modem

All three RB750 I have do the same thing - 17-120kbps throughput on WAN (10Mbps half duplex). Factory settings or just src-nat on WAN port give same results. Tried ROS 4.9 and 4.10. Which other version can I try? Nothing below 4.9 seems available for RB750…

If connected via another router (WAN 100Mbps fdx) , same configuration all three work just fine…

:confused:

Any suggestions?

PS: supout is not creating. ethernet stats are empty even though router is pushing some traffic:

[admin@MikroTik] /interface ethernet> print stat
                      name: ether1-gateway ether2-local-master ether3-local-sl>
              rx-broadcast:                0                   0              >
                  rx-pause:                0                   0              >
              rx-multicast:                0                   0              >
              rx-fcs-error:                0                   0              >
            rx-align-error:                0                   0              >
                   rx-runt:                0                   0              >
               rx-fragment:                0                   0              >
                     rx-64:                0                   0              >
                 rx-65-127:                0                   0              >
                rx-128-255:                0                   0              >
                rx-256-511:                0                   0              >
               rx-512-1023:                0                   0              >
              rx-1024-1518:                0                   0              >
               rx-1519-max:                0                   0              >
               rx-too-long:                0                   0              >
               rx-overflow:                0                   0              >
                  rx-bytes:                0                   0              >
              tx-broadcast:                0                   0              >
                  tx-pause:                0                   0              >
              tx-multicast:                0                   0              >
               tx-underrun:                0                   0              >
                     tx-64:                0                   0              >
                 tx-65-127:                0                   0              >
                tx-128-255:                0                   0              >
                tx-256-511:                0                   0              >
               tx-512-1023:                0                   0              >
              tx-1024-1518:                0                   0              >
               tx-1519-max:                0                   0              >
               tx-too-long:                0                   0              >
              tx-collision:                0                   0              >
    tx-excessive-collision:                0                   0              >
     tx-multiple-collision:                0                   0              >
       tx-single-collision:                0                   0              >
     tx-excessive-deferred:                0                   0              >
               tx-deferred:                0                   0              >
         tx-late-collision:                0                   0              >
                  tx-bytes:                0                   0              >

I figured it out: eth1 will not work with the modem- other ports work fine, at least with ROS 3.30 (I don’t have time to check other versions and I’ll stick with 3.30 since 4.x supout was failing and 3.x did not…)

Set the same MAC address as the “other” router has! :smiley:

Tried that :smiley:

UBR900 works with all other ports except eth1.

THEN WHERE IS THE PROBLEM??? :open_mouth:
Stick it in port 2-5, reconfigure the config and go get a beer!
It is amazing how people try to find problems where there are none.

Maybe problem with auto-negotiation on port one, disable it and set it manually.