SG500-52P problem with one port.

[MarcelSmal001]

Good day,

Please can someone assist me with this. I have a watchguard wireless device that is plugged into my SG500-52P access stack switch.

The problem I have with my wireless device is that it keeps on dropping the connection. Now I have the idea that STP is the problem but I am not sure.

I logged onto my switch and I see the following status msg's:

27-Feb-2014 16:21:00 %STP-W-PORTSTATUS: gi2/1/35: STP status Forwarding, aggregated (1)
27-Feb-2014 16:22:24 %LINK-W-Down:  gi2/1/35, aggregated (1)
27-Feb-2014 16:22:44 %LINK-I-Up:  gi2/1/35, aggregated (2)
27-Feb-2014 16:22:48 %LINK-W-Down:  gi4/1/23

I only need it to be on a native vlan 20 and not the extra one Vlan 226.

This is the running config of the interface where it is plugged into:

interface gigabitethernet2/1/35
 spanning-tree bpduguard enable
 switchport trunk allowed vlan add 226
 switchport trunk native vlan 20
 no macro auto smartport

Can anyone assist me with this as I cant seem to figure it out on my own.

[Aleksandra Dargiel]

Hi Marcel,

First of all I would check the MAC address table entry for this port several times, especially when it is dropping to understand if the issue is related to changing VLAN or something else.

Is there any SSID running on VLAN 226?

The log messages could be the root cause if your issue but also the result of something else for example AP disconnecting.

Is the AP powered by external source or PoE? What is the AP? 

RSTP or STP would normally erase MAC table entries when TCN BPDU messages are received by switch. You may want to ensure all end devices' ports are configured as edge device for STP settings so less TCN is generated.

Regards,

Aleksandra

[MarcelSmal001]

Hi Alexandra,

Thank you for the reply. When I logged into the switch and did a mac address table entry It stays there. I used my mobile phone to test this. And after the drop its not there. And as soon as there is data again the phone is connected to wifi.

No SSID's on vlan226 this is a voice vlan.

Its on POE. Watchguard Wireless AP.

[Aleksandra Dargiel]

Hi Marcel,

MAC table entry, when present shows in the correct VLAN 20?

Try to set up this port as access in vlan 20 only disable BPDU guard however since the AP might actually support STP.

Regards,

Aleksandra

[MarcelSmal001]

Hi Aleksandra,

When I do the MAC table entry every thing is VLAN20. For some reason I cant remove the following:

interface gigabitethernet2/1/35
 spanning-tree bpduguard enable
 switchport trunk allowed vlan add 226
 switchport trunk native vlan 20
 no macro auto smartport

Also see the PRTG output as a attachment.

Just one more input what can you tell me about the logs im getting:

 24-Mar-2014 19:07:13 %LINK-I-Up:  gi1/1/36
24-Mar-2014 19:07:18 %STP-W-PORTSTATUS: gi1/1/36: STP status Forwarding
24-Mar-2014 19:07:36 %LINK-W-Down:  gi1/1/36
24-Mar-2014 19:07:39 %LINK-I-Up:  gi1/1/36, aggregated (1)
24-Mar-2014 19:07:44 %STP-W-PORTSTATUS: gi1/1/36: STP status Forwarding, aggregated (1)
24-Mar-2014 19:07:47 %LINK-W-Down:  gi2/1/35
24-Mar-2014 19:08:07 %LINK-I-Up:  gi2/1/35
24-Mar-2014 19:08:12 %STP-W-PORTSTATUS: gi2/1/35: STP status Forwarding
24-Mar-2014 19:09:22 %LINK-W-Down:  gi3/1/19
24-Mar-2014 19:09:25 %LINK-I-Up:  gi3/1/19
24-Mar-2014 19:09:30 %STP-W-PORTSTATUS: gi3/1/19: STP status Forwarding

[Aleksandra Dargiel · Accepted solution]

Hi Marcel,

I am not entirely sure why would you have problem with removing vlans from trunk.

Is this action giving you an error?

Or are those settings reappearing automatically?

It would be good idea to look into the details so I would suggest you to open ticket with Cisco Small Business Support team: 

http://www.cisco.com/c/en/us/support/web/tsd-cisco-small-business-support-center-contacts.html

Aleksandra

[vyas.2020]

Hello MarcelSmal

What solution have you got from tac. It would be helpful for others.