Unable to connect to Core Switch

[Abayomi Smith]

Hello All,

I have a problem with extending the LAN on a client site . They are looking to extend the LAN with a 2960S-series switch. Already in place is a 4510 switch which the 2960 is connected to via fibre. The 2 switches are both set up but there is no connectivity as I cant ping between them or anything.

The management VLAN on the 2960 shows line up, protocol down, which I believe means the VLAN is enabled but there is a form of physical mismtach on the ports. I have attached the configs of both switches. I would appreciate if anyone can take a look and help out with what might be wrong. I feel it might be a problem with GBIC module compatibility. The SFP installed on both ends of the switch are GLC-SX-MMD. On the 4510, the SFP sits in a twingig converter (CVR-X2-SFP) but there is no light on it at all when the cables are plugged in.

I need to be sure its not a configuration issue. 

[tudortdk2012]

Hy Abayomi,

Well , I'm a fresh CCNP so my answer probably will not help you, but until someone will response...

Firt vlan 5 is up down because no interface is in  access vlan 5. from what i saw all the interface in access are for vlan 100. so i believe when you will configure an interface for vlan 5, it will be up up.

And another thing, from what i see on core, it has port-channel to connect to your extensio, maybe if you try to make a port-channel on the extension the ping will work.

I'm waiting a pro to answer your question.

Best regards,

Dragos Tudor

[Abayomi Smith]

Thanks a lot for your response dragos, if I understand you well, you are saying that the access ports should also have the management vlan enabled on them? If thats what you are saying, I don't think so, however of you are saying they should be enabled on the trunk ports, they have and the issue still remains.

[tudortdk2012]

Hy!

No no, the acces port should not have also the vlan 5, but vlan 5 will shown up down until you will configure a port with vlan 5. You can configure a single port with vlan 5 to see that. that will not influence  the ping . and i see the two switches are leased with a port-channel but i don-t see wich one is active and wich one is passive, and that i think is a big problem.

Best regards,

Dragos Tudor

[Jan Hrnko]

Hi Dragos,

Well it depends on the implementation as you can see here :

http://www.cisco.com/en/US/products/hw/switches/ps708/products_tech_note09186a0080160b14.shtml

You will eiter see interface vlan down, down or up,down.

But in these configuration files you can clearly see that a trunk is configured with vlan 5 allowed on it. Therefore I think that the problem will be not resolved by configuring an port associated with vlan 5.

Best regards,

Jan

[tudortdk2012]

Hy Jan,

Agree with you, but what do you say about port-channel configuration, i don't see what is active/passive.  maybe this is the problem...

Best regards

Dragos

[Jan Hrnko]

Hi Dragos,

thank you! Well keep on searching with me . Maybe it could be in port-channel configuration, better check out if the port-channel is formed if there is no spanning-tree instance for vlan 5.

Best regards,

Jan

[Abayomi Smith]

thanks for your help Jan( I have got a friend who is called Janko but shortens his name to Jan though I call him Janko all the time so I just assumed...lol)...upon issuing the command and checking I am still getting the same thing "no instance of spanning tree exist for vlan 5"....it proves it's more than spanning tree like u said...brought in new SFP's just to check but still no luck....

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[Jan Hrnko]

Hi Abayomi,

well in my experience interface vlan Up, Down is seen when STP is misconfigured. Make sure that STP for the management vlan is up and running!

sh spanning-tree vlan 5

(I believe that vlan 5 is your management vlan)

Hope that Helps.

Best regards,

Jan

[Abayomi Smith]

thanks a lot Janko, I get "no spanning tree info available for vlan 5" when I issue the command.

However on enabling it for vlan 5 and doing the show command to check, I still get the same thing, no spanning tree info available for vlan 5...dunno whether I need to enae it for the physical interface connecting to the core switch... What do u think?

[Jan Hrnko]

Hi,

you're welcome. Have you tried sh spanning-tree vlan 5 or sh spanning-tree interface vlan 5? Because I made an mistake and then I edited the post .

sh spanning-tree vlan 5 is what we need here.

Best regards,

Jan

[Abayomi Smith]

hi Janko, sorry I did it for int vlan 5. So for vlan 5, should the stp type be auto or IEEE?

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[Jan Hrnko]

Hi Abayomi,

First of all - how do you know the other form of my name?

And the second thing, would you be able to actually paste the output here?

I see in your configuration setting that you are running rapid-pvst. So the output should not show IEEE but rstp - if we are talking about Spanning tree mode.

Something like:

Switch#sh spanning-tree vlan 5
VLAN0005
  Spanning tree enabled protocol rstp

I'm still looking through the configuration files to see if something isn't wrong.

Best regards,

Jan

[Abayomi Smith]

Sorry Janko, do u have the syntax to enable it under vlan 5? When I do sh spanning-tree vlan 5, I get spanning-tree instance for Vlan 5 does not exist

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[Jan Hrnko]

Hi Abayomi,

Well there we have it! I hope so... If everything is fine and just somehow the vlan 5 is missing it can be added by issuing command:

Switch(config)#spanning-tree vlan 5

But I have a bad feeling something else is going on here. Because from the configuration files I see, It just seems to me that the switch should have created instance for vlan 5 automatically.

Best regards,

Jan