ESW540 switch no access to management interface

[luumanioro]

Hi,

I'm dealing with very strange situation here:) I have there ESW540 switches and I've recently changed management vlan and IP on all of them. Most of the time I can connect to them but recently I've noticed that I lose connection to management IP address for no reason. I can't access the web console or ping the management IP on each of these switches unless I disconnect one of them. 

The configuration is as follow:

- SW1 > SW2

- SW2 > SW3

- SW3 > SW1

- Trunks configured on each uplink interface

- Spanning Tree enabled on each uplink port - Rapid STP

- Fast Port enabled on each uplink port

Anyone had similar experience? Any idea what might be causing this problem?

Thank you for your help,

Luumanioro

[Aleksandra Dargiel]

Hi Luumanioro,

From what you are describing it looks like you have layer 2 loop. Please enable STP and disable Fast Port on the uplink ports. This should prevent loops and block second link on your network.

Regards,

Aleksandra

[luumanioro]

Same issue, Fast Port disabled on all uplinks and I can now access only one switch, this time this is SW2. Before reconfiguration I could access only SW3. I have three other Catalyst switches but in the different location connected exactly in the same way but without Fast Port and all works fine, but these ESW540 just don't want to work as they should! It's very strange that I lose connection to these switches in very random way.

[Aleksandra Dargiel]

Hi Luumanioro,

Assuming that they do have different IP addresses I would try to do packet capture to see if the ARP response is correct and what is ICMP message on your echo request. If this one would not really bring any light into this issue, please open ticket with Small Business Support Center Team:

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

Regards,

Aleksandra

[luumanioro]

Yes, they all have different static IP addresses. ARP seems to response with the correct message but since I can't even ping the device I get "No response seen" in ICMP.

Very odd I though that it might be something to do with my DHCP failover configuration which for some reasons did replicate all scopes properly, I fixed it but it didn't resolve issues with switches.

[Aleksandra Dargiel]

Hi Luumanioro,

It would be good idea to follow the MAC addresses of the switches in mac address tables when issue occurs.

Regards,

Aleksandra