I will listen in on this ..
We see these A LOT!! (like a zillion times a day) and I should be much mistaken if all the cables/plugs were faulty everywhere in the installation ..
Any news ?
(SW: MS 11.30)
I have got the same issue on different LANs with MS225 switches with MS 11.30 software. But only on client-ports not on uplink ports. First I thought it´s an power saving issue on the clients. Apple Mac do have the most issues.
Hi @redsector ..
I only have AP's connected to the ports doing this ..
No issues on uplink ports as well as You observe ..
Will be interesting to hear what the Engineers say ?
Accesspoints from Cisco (classic) and Cisco Meraki (MR32, MR33, MR34, MR42, MR42E, MR52, MR45) are stable connected (trunk) to my Meraki network ports (software MS11.30). Also the uplink ports (to Cisco classic and to Merak) are stable.
Only clients (access) from Dell and Apple are having this issue.
This really sounds the same as the MAC flap issue on 11.x.
Or the MAC flap issue is the same as this.
If it's the MAC flap issue then the STP messages are just a byproduct of the port going down. If this is a separate and distinct issue with the BPDUs as someone mentioned then the STP messages are relevant.
I can say that, when I went to 11.22 my Cisco IP phones were going offline like crazy. I have Cisco 3905s and 8811s, also ATA-190s for analog bridge.
The MR34 and MR52 access points that I have were stable throughout the issues.
I had to call support by phone to get someone to move the case forward. The phone tech said that he noticed 97% cpu usage on my core switch. I wish they expose that info in the portal, all I can see as far as health for the switch is a nice green "Healthy", meanwhile CPU is at 97% and ports are flapping in the logs. He thinks the CPU might be causing ports to go down and then generating the UDLD and STP alerts. He asked me to update to the latest (11.30) which I did this morning, but still see the same flapping in the logs, and I am waiting to a support tech to tell me what the CPU looks like now. He also cannot explain what he is seeing and thought it might be a performance bug (hence he asked me to upgrade).
To clarify, in the logs the ports that are flapping are the 16 ports that connect 3 switches to my root switch and they are only alerting from the perspective of the other 3 switches, the root switch sees no issues with the his end of those 16 connections (its own 16 ports). There are another 8 ports that connect 2 of those switches to the secondary root switch, but those are disabled (correctly) by STP and are not seen flapping in the logs. These ports are aggregated what I usually see in the logs is that a few of the individual ports alarm about becoming unidirectional (alert by UDLD, no enforcement, means BPDU packets only going in one direction), and then back to bidirectional right away. Then I see STP cycle the entire aggregate port between root, alternate or disabled. This is constantly happening on the logs, but I only see a measurable outage when lots of UDLD alerts appear together.
I'd be interesting in seeing if that high CPU continues, and that does seem like it could cause the port flap issue.
I wish we could see that in the dashboard.
According to the tech CPU was still high so he disabled some DNS inspection:
"I did notice a spike in the CPU after the update as well. I have disabled DNS and MDNS inspection on the core switch " SW1A "since we had noticed an unusual amount of DNS traffic during the pcaps taken on the switch."
I am seeing less of the UDLD alerts, but the 3-4 alerts from the last few days have caused network blips and alerts to come out at the same time. I do still see a ton of STP alerts about it changing the aggregate ports that interconnect the 4 switches, something like 4-25 times per hour with no alerts about network issues.
I also noticed that there is already a new version 11.31 thought it doesnt list this particular issue, here are the release notes:
Any chance you have found a solution with Meraki yet? We seem to be having the same issue within our organization as well. Meraki Support is telling us we have bad cables, but we have already ruled that out as a possibility.
Our next step is going to be replacing it with a regular Cisco switch and see if the problem persist.
I did update to 11.31 this morning, but the STP flapping continues. Noticed this upgrade did not reboot the switches, and did not show a progress bar on the local GUI of each switch as it usually does. Also, nothing on the logs about the firmware upgrade. I really wish Meraki would make the logs more useful.
Meraki tech suggested the follwing
Hi @Matttt -.-
We still see lots of these ..
And we also tried the new switch sw, but reverted, since it did no good in the matter.
It seems that uplinks/trunks and workstation links are affected and not selective 😉
All switch-types are affected.
It bursts 10-15 entries in the log in each occurance.
We have got MS220 and MS225 switches with MS11.31 software. No uplinks are affected (to Cisco "classic" and Maraki). Only HP-inkjets, Apple computers and Dell notebooks with dockingstations are affected.
This is the response we received when I was having the issue back in the Summer.The issue eventually stopped without me making any changes to our network or the firmware. Seems to me they have yet to find the bug that's causing all the problems everyone is experiencing.