Bridge STP Issue (Keeps discarding, learning, forwarding)

RouterOS General
1

Hi,

I have a bridge that is bound to my customers and these bridge also contains my antennas. On Port 9 (which is my Mimosa PtP bakchaul device) I keep getting the error below;

My bridge config;

Flags: X - disabled, R - running 
 0 R ;;; PPPoE Bridge
     name="pppoe+hs" mtu=1500 actual-mtu=1500 l2mtu=1590 arp=enabled 
     arp-timeout=auto mac-address=4C:5E:0C:**:**:** protocol-mode=rstp 
     fast-forward=no igmp-snooping=no auto-mac=yes ageing-time=5m 
     priority=0x8000 max-message-age=20s forward-delay=15s 
     transmit-hold-count=6 vlan-filtering=no dhcp-snooping=no

and this is my wan bridge;

 1 R name="wanbridge" mtu=auto actual-mtu=1500 l2mtu=1590 arp=enabled 
     arp-timeout=auto mac-address=4C:5E:0C:**:**:** protocol-mode=rstp 
     fast-forward=no igmp-snooping=no auto-mac=yes ageing-time=5m 
     priority=0x8000 max-message-age=20s forward-delay=15s 
     transmit-hold-count=6 vlan-filtering=no dhcp-snooping=no

Ethernet port that I’m having issue with;

Flags: X - disabled, R - running, S - slave 
 0 RS ;;; MIMOSA_HQ
      name="ether9" default-name="ether9" mtu=1500 l2mtu=1590 
      mac-address=4C:5E:0C:**:**:** orig-mac-address=4C:5E:0C:**:**:** 
      arp=enabled arp-timeout=auto loop-protect=default loop-protect-status=off 
      loop-protect-send-interval=5s loop-protect-disable-time=5m 
      auto-negotiation=yes advertise=10M-full,100M-full,1000M-full 
      full-duplex=yes tx-flow-control=auto rx-flow-control=auto speed=100Mbps 
      bandwidth=unlimited/unlimited

Current status of Port 9 (Mimosa)

/interface bridge port monitor
numbers: 4
            interface: ether9
               status: in-bridge
          port-number: 6
                 role: designated-port
            edge-port: no
  edge-port-discovery: yes
  point-to-point-port: yes
         external-fdb: no
         sending-rstp: yes
             learning: yes
           forwarding: yes

Right after this happens, I see my customers tries to re-auth on PPPoE server which closes previous connections and re-iniates a new one.

Could this be a cable issue or any configuration issue?

Thanks in advance for any suggestion, this is very important to me.

2

It seems MikroTik tries to build the RSTP tree but it can’t due to the mimosa antenna.
Is your Bridge, a root bridge? you will see that in status.

3

Thanks for response Zacharias,

No I have 2 bridges, first one is WAN Bridge and there is actually only 1 port assigned to it, and this is root and second one is the bridge I mentioned above. (I updated my post and added both bridge config)

4

Lower the BPDU value of your Bridge so it becomes a root bridge… make it 7000 instead of 8000

5

Is the problem about root bridge? If I make this bridge a root bridge, would it solve the STP discarding issue?

Thank you!

6

Probably not.. but why dont you test it? It will take you less than 10 seconds to change the BPDU value…!

7

Thanks a lot for response, yet again :slight_smile: But unfortuantely that didn’t solve the issue :frowning:

8

It keeps discarding for a reason… Maybe you should check your configuration on the mimosa…
I would test if setting sending-rstp: no and learning: no
Would make any difference…

You can see here what those values mean https://wiki.mikrotik.com/wiki/Manual:Spanning_Tree_Protocol

Basically setting sending rstp to no will result in no more BPDU messages send from that port. Learning equals to no will stop the port from learning mac addresses…

Test one at a time…