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Unable to connect to Core Switch

Abayomi Smith
Level 1
Level 1

‎09-21-2012 05:25 AM - edited ‎03-07-2019 09:00 AM

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. 

Labels:
135443-CORE_SW.txt.zip
135444-Lan EXT_SW.txt.zip
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40 Replies 40

Abayomi Smith
Level 1
Level 1
In response to Jan Hrnko

‎09-22-2012 05:54 AM

Hi Jan, Dragos

Many thanks for yesterday. I have been going through the show tech output of the access switch. I posted some of the output below.

------------------ show etherchannel summary ------------------


Flags:  D - down        P - bundled in port-channel
        I - stand-alone s - suspended
        H - Hot-standby (LACP only)
        R - Layer3      S - Layer2
        U - in use      f - failed to allocate aggregator

        M - not in use, minimum links not met
        u - unsuitable for bundling
        w - waiting to be aggregated
        d - default port


Number of channel-groups in use: 1
Number of aggregators:           1

Group  Port-channel  Protocol    Ports
------+-------------+-----------+-----------------------------------------------
4      Po4(SD)          -        Gi1/0/49(D) Gi1/0/50(D)

From this, it doesnt show any protocol (PApg or LACP) for etherchannel and i also get this output for my trunkports under show interfaces switchports

Name: Gi1/0/49
Switchport: Enabled
Administrative Mode: trunk
Operational Mode: down (suspended member of bundle Po4)
Administrative Trunking Encapsulation: dot1q
Negotiation of Trunking: On
Access Mode VLAN: 1 (default)
Trunking Native Mode VLAN: 1 (default)
Administrative Native VLAN tagging: enabled
Voice VLAN: none
Administrative private-vlan host-association: none
Administrative private-vlan mapping: none
Administrative private-vlan trunk native VLAN: none
Administrative private-vlan trunk Native VLAN tagging: enabled
Administrative private-vlan trunk encapsulation: dot1q
Administrative private-vlan trunk normal VLANs: none
Administrative private-vlan trunk associations: none
Administrative private-vlan trunk mappings: none
Operational private-vlan: none
Trunking VLANs Enabled: 5,100,101
Pruning VLANs Enabled: 2-1001
Capture Mode Disabled
Capture VLANs Allowed: ALL

Protected: false
Unknown unicast blocked: disabled
Unknown multicast blocked: disabled
Appliance trust: none

Name: Gi1/0/50
Switchport: Enabled
Administrative Mode: trunk
Operational Mode: down (suspended member of bundle Po4)
Administrative Trunking Encapsulation: dot1q
Negotiation of Trunking: On
Access Mode VLAN: 1 (default)
Trunking Native Mode VLAN: 1 (default)
Administrative Native VLAN tagging: enabled
Voice VLAN: none
Administrative private-vlan host-association: none
Administrative private-vlan mapping: none
Administrative private-vlan trunk native VLAN: none
Administrative private-vlan trunk Native VLAN tagging: enabled
Administrative private-vlan trunk encapsulation: dot1q
Administrative private-vlan trunk normal VLANs: none
Administrative private-vlan trunk associations: none
Administrative private-vlan trunk mappings: none
Operational private-vlan: none
Trunking VLANs Enabled: 5,100,101
Pruning VLANs Enabled: 2-1001
Capture Mode Disabled
Capture VLANs Allowed: ALL

Protected: false
Unknown unicast blocked: disabled
Unknown multicast blocked: disabled
Appliance trust: none

0 Helpful

tudortdk2012
Level 1
Level 1
In response to Abayomi Smith

‎09-22-2012 07:05 AM

Hy,

Hmmm, interesting - Operational Mode: down (suspended member of bundle Po4)-

Can you copy the output from "sh int X status" for the four interfaces wich are in the etherchannel please? I want to see someting because:

"The interfaces in a port channel must share the same speed and duplex, trunking encapsulation(if not trunking – the same access vlan), the same STP cost per per VLAN, and no ports can have SPAN configured.   "

Best regards,

Dragos

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Jan Hrnko
Level 4
Level 4
In response to Abayomi Smith

‎09-21-2012 08:10 AM

Abayomi,

what about allowed vlans on the trunk between these two switches? I don't see native vlan (vlan 1) to be allowed here, or any native vlan configured which would be allowed on this trunk.

Maybe the port-channels aren't even formed! Such as Dragos suggested.

Try to verify this by commands such as

show etherchannel summary

or

show interfaces port-channel 4

Best regards,

Jan

0 Helpful

Abayomi Smith
Level 1
Level 1
In response to Jan Hrnko

‎09-21-2012 08:21 AM

Thanks Jan for your help, it's very much appreciated....there are other switches connected to the core switch. These switches have wireless AP's connected to them for laptop users...now there is no native vlan allowed on those trunks to those switches

Sent from Cisco Technical Support iPhone App

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Abayomi Smith
Level 1
Level 1
In response to Jan Hrnko

‎09-21-2012 08:22 AM

The interface port channel are formed but it's just showing down, down(not connect)

Sent from Cisco Technical Support iPhone App

0 Helpful

tudortdk2012
Level 1
Level 1
In response to Abayomi Smith

‎09-21-2012 08:36 AM

The port-channel appear there like an interface once you've created the etherchannel

But from the "show run" is not complete configured

channel-protocol lacp

channel-group 4 mode active

I think you must put these comands on the interfaces of the switches, but on the extension switch it must be "passive" instead "active".

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Jan Hrnko
Level 4
Level 4
In response to tudortdk2012

‎09-21-2012 08:42 AM

Dragos,

I think that it could be configured just likethat:

channel-group 4 mode on

It will force the channeliling on and don't negotiate with other side. It should work however negotiation is better in the first stages of configuration - because if it doesn't work, you know there is a problem.

Best regards,

Jan

0 Helpful

tudortdk2012
Level 1
Level 1
In response to Jan Hrnko

‎09-21-2012 08:47 AM

Agree again

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Abayomi Smith
Level 1
Level 1
In response to Jan Hrnko

‎09-21-2012 09:45 AM

yes Jan, I agree it can be configured like that. So that shouldn't be an issue. I see the GBIC modules when I issue a sh inventory, so I know it's not an issue with that. However I will need to check that on the core switch, unfortunately I have had

to leave site to attend to something else...will check on Monday. Thanks guys very much appreciated, Dragos and Jan. will post the show tech for any clues

Sent from Cisco Technical Support iPhone App

0 Helpful

Jan Hrnko
Level 4
Level 4
In response to Abayomi Smith

‎09-21-2012 08:39 AM

Abayomi,

then it means that the port-channels are not formed,  therefore spanning-tree instance for vlan 5 does not exists and cannot  be created and that's most likely why the management vlan is up,down. So  Dragos was going in the right direction!

There is one more thing if you are not sure about the GBIC compatibility. You can run

sh diag

command. If it outputs  "Unknown" instead of description of the module, it is not supported.

Best regards,

Jan

0 Helpful

tudortdk2012
Level 1
Level 1
In response to Jan Hrnko

‎09-21-2012 12:27 PM

Hy!

Another quick question: are you sure that you cabled fine the two switches? (gi1/0/49 with 5/1 and 1/0/50 with 6/1) because protocol down down , from what i know, it'a a physical layer problem. and i see the "channel-group 4 mode on" command has been already issued on both switches. and if everything is fine, do a debug. i'm not sure if tengigabit is understandig well with gigabit (maybe is a speed mismatch).

Best regards,

Dragos

0 Helpful

jimmysands73_2
Level 5
Level 5
In response to tudortdk2012

‎09-22-2012 06:33 AM

And

1)  Have you verified via links lights or sh int that you have layer 1 connectivity?

2)  Have you verified int vlan 1 is shut down on the 2960 and gone into int vlan5 on the lan sw and performed a no shut?  On vlan1 you should have a no shut since I believe the 2960 can only have one active svi (could be wrong, comapring them to the 2950s here)..

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Abayomi Smith
Level 1
Level 1
In response to jimmysands73_2

‎09-22-2012 07:28 AM

Hi Jimmy,

Many thanks for your response. Everything is properly connected. Fibre patch cables are new and fibre patch panel connection was put in place a couple of days ago and has been tested and works all ok, SFP's have been changed but still no lights come on both switches. It does look like a mismatch somewhere but not been able to find it yet. I have checked to make sure vlan 5 isnt shut and and done a no shut under vlan 1, still no good.

0 Helpful

Abayomi Smith
Level 1
Level 1
In response to tudortdk2012

‎09-22-2012 07:33 AM

Hi Dragos,

Thanks a bunch for yesterday. Happy you are still following up on this.

Please find output as requested below.

Hi Dragos,

Nice to see you are still following up on this. as regards your request please find output below.

------------------ show interfaces status ------------------

Port      Name               Status       Vlan       Duplex  Speed Type
Gi1/0/1   <>     notconnect   100          auto   auto 10/100/1000BaseTX
Gi1/0/2   <>     notconnect   100          auto   auto 10/100/1000BaseTX
Gi1/0/3   <>     notconnect   100          auto   auto 10/100/1000BaseTX
Gi1/0/4   <>     notconnect   100          auto   auto 10/100/1000BaseTX
Gi1/0/5   <>     notconnect   100          auto   auto 10/100/1000BaseTX
Gi1/0/6   <>     notconnect   100          auto   auto 10/100/1000BaseTX
Gi1/0/7   <>     notconnect   100          auto   auto 10/100/1000BaseTX
Gi1/0/8   <>     notconnect   100          auto   auto 10/100/1000BaseTX
Gi1/0/9   <>     notconnect   100          auto   auto 10/100/1000BaseTX
Gi1/0/10  <>     notconnect   100          auto   auto 10/100/1000BaseTX
Gi1/0/11  <>     notconnect   100          auto   auto 10/100/1000BaseTX
Gi1/0/12  <>     notconnect   100          auto   auto 10/100/1000BaseTX
Gi1/0/13  <>     notconnect   100          auto   auto 10/100/1000BaseTX
Gi1/0/14  <>     notconnect   100          auto   auto 10/100/1000BaseTX
Gi1/0/15  <>     notconnect   100          auto   auto 10/100/1000BaseTX
Gi1/0/16  <>     notconnect   100          auto   auto 10/100/1000BaseTX
Gi1/0/17  <>     notconnect   100          auto   auto 10/100/1000BaseTX
Gi1/0/18  <>     notconnect   100          auto   auto 10/100/1000BaseTX
Gi1/0/19  <>     notconnect   100          auto   auto 10/100/1000BaseTX
Gi1/0/20  <>     notconnect   100          auto   auto 10/100/1000BaseTX
Gi1/0/21  <>     notconnect   100          auto   auto 10/100/1000BaseTX
Gi1/0/22  <>     notconnect   100          auto   auto 10/100/1000BaseTX
Gi1/0/23  <>     notconnect   100          auto   auto 10/100/1000BaseTX
Gi1/0/24  <>     notconnect   100          auto   auto 10/100/1000BaseTX
Gi1/0/25  <>     notconnect   100          auto   auto 10/100/1000BaseTX
Gi1/0/26  <>     notconnect   100          auto   auto 10/100/1000BaseTX
Gi1/0/27  <>     notconnect   100          auto   auto 10/100/1000BaseTX
Gi1/0/28  <>     notconnect   100          auto   auto 10/100/1000BaseTX
Gi1/0/29  <>     notconnect   100          auto   auto 10/100/1000BaseTX
Gi1/0/30  <>     notconnect   100          auto   auto 10/100/1000BaseTX
Gi1/0/31  <>     notconnect   100          auto   auto 10/100/1000BaseTX
Gi1/0/32  <>     notconnect   100          auto   auto 10/100/1000BaseTX
Gi1/0/33  <>     notconnect   100          auto   auto 10/100/1000BaseTX
Gi1/0/34  <>     notconnect   100          auto   auto 10/100/1000BaseTX
Gi1/0/35  <>     notconnect   100          auto   auto 10/100/1000BaseTX
Gi1/0/36  <>     notconnect   100          auto   auto 10/100/1000BaseTX
Gi1/0/37  <>     notconnect   100          auto   auto 10/100/1000BaseTX
Gi1/0/38  <>     notconnect   100          auto   auto 10/100/1000BaseTX
Gi1/0/39  <>     notconnect   100          auto   auto 10/100/1000BaseTX
Gi1/0/40  <>     notconnect   100          auto   auto 10/100/1000BaseTX
Gi1/0/41  <>     notconnect   100          auto   auto 10/100/1000BaseTX
Gi1/0/42  <>     notconnect   100          auto   auto 10/100/1000BaseTX
Gi1/0/43  <>     notconnect   100          auto   auto 10/100/1000BaseTX
Gi1/0/44  <>     notconnect   100          auto   auto 10/100/1000BaseTX
Gi1/0/45  <>     notconnect   100          auto   auto 10/100/1000BaseTX
Gi1/0/46  <>     notconnect   100          auto   auto 10/100/1000BaseTX
Gi1/0/47  <>     notconnect   100          auto   auto 10/100/1000BaseTX
Gi1/0/48  <>     notconnect   100          auto   auto 10/100/1000BaseTX
Gi1/0/49  << connecttion to  notconnect   1            auto   auto 1000BaseSX SFP
Gi1/0/50  << connecttion to  notconnect   1            auto   auto 1000BaseSX SFP
Gi1/0/51                     notconnect   1            auto   auto Not Present
Gi1/0/52                     notconnect   1            auto   auto Not Present
Po4       << connection to M notconnect   unassigned   auto   auto
Fa0                          notconnect   routed       auto   auto 10/100BaseTX

0 Helpful

tudortdk2012
Level 1
Level 1
In response to Abayomi Smith

‎09-22-2012 07:45 AM

please give the output from : sh int Gi1/0/49 status and sh int Gi1/0/50 status from Lan_EXT_SW and sh int Te5/1 status and sh int Te6/1 status from Core_SW

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