topic Re: STP BPDU Drop in ExtremeSwitching (EXOS/Switch Engine)

STP BPDU Drop

cback85 — Thu, 28 Jan 2021 08:41:27 GMT

I am really new to STP on Extreme switches but I am seeing this error fill the logs. They are connected up to core Cisco switches I believe using PVST+ between the switches.

01/27/2021 18:38:31.41 <Erro:STP.InBPDU.Drop> Port=10: No associated STP port for STP Domain tag 1 (Rate-limited)
01/27/2021 18:36:31.41 <Erro:STP.InBPDU.Drop> Previous message repeated 10 additional times in the last 108 second(s)

Re: STP BPDU Drop

cback85 — Thu, 28 Jan 2021 08:50:46 GMT

Here is some more info. I see s0 is the only one in 802.1D mode?

s0(enable), Tag=0001, Mode=802.1D, State=FORWARDING

s18(enable), Tag=0018, Mode=PVST+, State=FORWARDING

s20(enable), Tag=0020, Mode=PVST+, State=FORWARDING

s706(enable), Tag=0706, Mode=PVST+, State=FORWARDING

s708(enable), Tag=0708, Mode=PVST+, State=FORWARDING

s709(enable), Tag=0709, Mode=PVST+, State=FORWARDING

s720(enable), Tag=0720, Mode=PVST+, State=FORWARDING

s721(enable), Tag=0721, Mode=PVST+, State=FORWARDING

s723(enable), Tag=0723, Mode=PVST+, State=FORWARDING

s95(enable), Tag=0095, Mode=PVST+, State=FORWARDING

s96(enable), Tag=0096, Mode=PVST+, State=FORWARDING

s97(enable), Tag=0097, Mode=PVST+, State=FORWARDING

s999(enable), Tag=0999, Mode=PVST+, State=FORWARDING

Re: STP BPDU Drop

DeoHeo — Thu, 28 Jan 2021 20:51:36 GMT

What STP mode is configured on the other switches on VLAN 1?

Re: STP BPDU Drop

cback85 — Fri, 29 Jan 2021 02:08:23 GMT

I believe on the Cisco it’s PVST+ as well

Re: STP BPDU Drop

cback85 — Fri, 29 Jan 2021 08:15:51 GMT

We decided to remove STP. Using ELRP instead on Default VLAN 1. Still getting BPUD error but not affecting anything so we decided to just do a log filter so the log wouldn’t overfill.

Re: STP BPDU Drop

DeoHeo — Mon, 01 Feb 2021 22:44:31 GMT

Is the issue solved for you? If not can you send me the VLAN configuration of the EXOS switch? The VLAN 1 configuration is enough.

Re: STP BPDU Drop

cback85 — Tue, 02 Feb 2021 00:40:51 GMT

Unfortunately I can’t send you the config as it was for a customer but yes the issue is solved removing STP and using ELRP instead on the Extremes. Still got the BPDU error but like I said we just did a log filter.

Re: STP BPDU Drop

RobertWilkinson — Mon, 15 Mar 2021 16:44:03 GMT

Does anyone have any other thoughts on how to restrict BPDU’s from coming into the network other than disabling STP?

I understand how disabling STP will work and i understand the ELRP feature being used instead of STP however i have a customer who does not currently have ELRP configured on any of the switches (there are about 137 of them) and i don’t want to adopt something i have not tested myself.

I’ve seen old cases on here from around 7 years ago regarding applying an ACL on ingress to the port with a counter but was also wondering is that still a valid means (mainly because its not clear on a port that an ACL is applied so unless you go looking for it then you will never see it).

What about using the TCN Restrict feature within STP?

Re: STP BPDU Drop

Tomasz — Mon, 22 Mar 2021 23:30:02 GMT

Hi Robert,

What’s the network topology?

Just food for thoughts: if the network doesn’t have any redundant connections that could be dealt using STP/LACP/MLAG/EAPS and you only aim to save access ports from loops I’d consider ELRP. Recently they’ve added some hardware assist to it so it can be even as low as 3ms of loop detection interval.

Hope that helps,

Tomasz