MS120 MAC Address/Port Table Incorrect

[Crocker]

I've got an MS120 telling me it sees a MAC address on Port 57 (which is actually on port 9). Several other entries are supposedly on ports 52-54 as well.

Thing is, this thing only has 48 ethernet ports + 4 SFP slots. None of the SFP slots are in use.

Something buggy with the dashboard today?

EDIT: This is happening on at least four different MS120's at separate locations. Neato.

[alemabrahao]

What version are you running? Have you opened a support case?

[Crocker]

14.33.1, no support case just yet.

[alemabrahao]

There are a lot of known issues with this version. I can try to update to the last stable version.

KNOWN ISSUES

• Stacks with a large number of LACP bundles (10+) may fail to initialize stack ports properly requiring additional reboots to regain connectivity
• MA-SFP-1GB-TX modules may fail to be detected after link loss (always present)
• Port modules may show incorrect information due to incorrectly reading CDP information
• Stack members may go offline after a stacking cable is reconnected requiring a power cycle (present since MS 12)
• MS120 in rare instances will not be able to perform packet captures until rebooted (predates MS 12.28)
• MS210/250 series switches may fail to relearn client MACs on ports that have access policies configured (present since MS 12)
• Links being established on an MS120 can result in neighboring ports to flap (present since MS 11)
• In very rare instances, MS120 series switches will reboot every 10 min (present since MS 12)
• Enabling Combined Power on MS350/355 switches results in events being logged once per minute (present since MS 11)
• Stack members are not being marked to update their configuration when changes are made on other members
• mGig switches will have an amber light for all physical ports that do not negotiate to the highest supported speed. Dashboard will continue showing a light green status for all ports above 100Mbps. Example, MS355 switch ports will incorrectly show an amber light for 1G, 2.5G, and 5G, but will show a green light for 10G.
• Cable test tool returns wrong pairs for 100Mbps connections (predates MS 12)
• Broadcast types of traffic can leak into the Guest VLAN if a port that fails authentication has a Voice VLAN configured, and dashboard has a Guest VLAN defined (present since MS 11)
• MS120s switch ports with MAB authentication may randomly deauthenticate clients. In order to resume client authentication on that port, a switch reboot is required (present since MS 12)
• MS350-24X and MS355 series switches do not negotiate UPoE over LLDP correctly (predates MS 10)
• Ports with an odd-numbered MTU value fail to initialize for MS120/125 series switches (predates MS 11)
• When an SFP module is inserted/removed on MS420/425 series switches, BPDUs can be delayed leading to STP transitions in the network (predates MS 12)

[RaphaelL]

Same here. MS120-8P  

Clients are shown on port 49-53 despite having only 8+2 ports.  Running MS15.21.1 ( latest firmware ). 

We should open a ticket about this.

[Crocker]

Thanks for confirming it's not just something weird that only we are seeing. I've opened a case with support. If any Meraki folks are haunting the forums and want to take a look, this is case #09582507.

[alemabrahao]

That's why I prefer the good old CLI.

[PhilipDAth]

Come on boomer.  Haha.  🙂

[Crocker]

Had a little back and forth with support about rebooting switches and updating from MS14.X to MS15.X. Was able to show them a reboot has no effect, and that this issue is present on both flavors of MS software.

The MS team is aware of the problem and are looking into it.

[Crocker · Accepted solution]

Got an update on my ticket yesterday that this issue has been resolved. After spot checking a few of my MS120's, it looks like this has been addressed.

[RaphaelL]

Yes. Also resolved on my side.

[dm-eagle]

I see this often on my MS225s