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RSTP Constant logging?

Fri Aug 20, 2021 9:47 pm


I've got a Mikrotik switch, 960PGS, in my engineering lab using ROS 6.44.6.

I do radio testing work, and often configure and reconfigure this network.

Something I just noticed, is that there is a log entry every minute...

Aug/20/2021 13:55:14 interface,warning ether3: bridge port received packet with own address as source address (6c:3b:6b:8d:9e:a6), probably loop
Aug/20/2021 13:56:14 interface,warning ether3: bridge port received packet with own address as source address (6c:3b:6b:8d:9e:a6), probably loop

Looking at this switch however, the above MAC isn't the MAC of ether3. That is the MAC of ether1.

There IS a loop in this network on the switch. It's between ether3 & ether 4. RSTP is configured to break that loop. And, RSTP BPDU packets that are output are DROPPED from ether1,2, 5 and the SFP port. Those ports shouldn't be outputting BPDU packets. This leaves ether3 & ether4. A BPDU packet from ether3 should only show up on ether4 and visa-versa. In addition, the RSTP status for ether4 is reporting =forwarding=false= so the RSTP IS funcitioning as it's supposed to, breaking that loop, and I see no packet storming or anything to indicate there is still a loop.

What I had found, was that this switch had stopped logging, because the flash drive was filled up, and had only 16.0K free. All these log files were filled up with that same log entry from above....over, and over, and over again, each minute.

Is this the standard thing for RSTP to make a log entry every minute while it's actively blocking something?!?!

Is there any way to stop this log entry?

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Re: RSTP Constant logging?

Sat Aug 21, 2021 12:27 pm

Fixed in 6.47 (stable) and 6.46.7 (long-term) onwards
*) discovery - do not send discovery packets on interfaces that are blocked by STP;
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Re: RSTP Constant logging?

Wed Nov 23, 2022 5:24 pm

Hello, Sirs.

I found the same error message in a RB4011 Logs Window. This Issue appears to be someone missconnected a UTP cross-cable in two ports of the same switch, you know, connecting Tx pins to Rx Pins in the same UTP cable makes packets to be sent out the port and received again in the same port of the router, or by connecting a UTP cable in two access ports of the same VLAN

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