Re: A core switch CANNOT see a WS-C2960S-48TS-S when i do show c

Jacob Gwangwa · ‎09-25-2012

Hi there.

I'm having a strange issue here. I just installed a WS-C2960S-48TS-S and connected it to the core switch WS-C6509-V-E.

CDP is enabled on both devices. When i do show cdp neighbor on my WS-C6509-V-E i cannot see the WS-C2960S-48TS-S in my neighbor table.

But on the WS-C2960S-48TS-S, when i do show cdp neighbor i can see the WS-C6509-V-E.

Note everything works fine its just that i'm worried as to why my WS-C6509-V-E cant see the WS-C2960S-48TS-S as its neighbor.

What i've tried thus far.....

on the interface level for both device cdp is enable and also in the global.

Please help me resolve this issue..

I would like to thank you in anticipation of your urgernt response

Regards,

Jacob

Alessio Andreoli · ‎09-25-2012

Hi Jacob,

i would tell you to check if the native vlan is the same and if the negotiation resulted in full-duplex. If you could post the interfaces which are connected, this would be great. Did you test the cable?

test cable-diagnostics tdr

google for it and you will find sme post from NetPro (this forum) explaining exactly how to do it. From Joseph or Reza if i am not wrong.

For sake of testing , a show interface switchport could help too.

Hope this helps

Alessio

Jacob Gwangwa · ‎09-25-2012

Hi Alessio

Thank you for your response.

From the 2960 see results below;

avrb-south-asw-8#sh int g0/49 status

Port      Name               Status       Vlan       Duplex Speed Type
Gi0/49    ***CVSS1-JRO connected    trunk      a-full a-1000 1000BaseSX SFP
avrb-south-asw-8#sh cdp n
avrb-south-asw-8#sh cdp neighbors de
avrb-south-asw-8#sh cdp neighbors detail | in CVSS1-JRO
Device ID: CVSS1-JRO
avrb-south-asw-8#sh cdp neighbors detail
-------------------------
Device ID: CVSS1-JRO
Entry address(es):
IP address: removed Platform: cisco WS-C6509-V-E, Capabilities: Router Switch IGMP
Interface: GigabitEthernet0/49, Port ID (outgoing port): GigabitEthernet1/2/27
Holdtime : 124 sec

Version :
Cisco IOS Software, s72033_rp Software (s72033_rp-ADVIPSERVICESK9_WAN-VM), Version 12.2(33)SXI2a, RELEASE SOFTWARE (fc2)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2009 by Cisco Systems, Inc.
Compiled Tue 01-Sep-09 20:22 by prod_rel_team

advertisement version: 2
VTP Management Domain: ''
Native VLAN: 1
Duplex: full
Management address(es):
IP address: removed

avrb-south-asw-8#

From the 6509 see results below;

CVSS1-JRO#sh cdp neighbors
Capability Codes: R - Router, T - Trans Bridge, B - Source Route Bridge
S - Switch, H - Host, I - IGMP, r - Repeater, P - Phone,
D - Remote, C - CVTA, M - Two-port Mac Relay

Device ID        Local Intrfce     Holdtme    Capability Platform Port ID
avrb-south-asw-9 Gig 2/2/5         133             R S I WS-C4507R Gig 3/2
avrb-south-asw-9 Gig 1/2/24        130             R S I WS-C4507R Gig 3/1
avrb-south-asw-6 Gig 2/2/6         172              S I   WS-C2960G Gig 0/48
avrb-south-asw-6 Gig 1/2/6         166              S I   WS-C2960G Gig 0/47
avrb-north-asw-1 Gig 2/2/11        176             R S I WS-C4510R Gig 1/4
avrb-north-asw-1 Gig 1/2/11        167             R S I WS-C4510R Gig 1/3
avrb-north-asw-2 Gig 2/2/12        151             R S I WS-C4506 Gig 2/4
avrb-north-asw-2 Gig 1/2/12        151             R S I WS-C4506 Gig 2/3
JAE0917AL81(jp-r1r17-asw-2)
                 Gig 1/2/16        155              T S   WS-C2948G 2/51
JAE0917AL81(jp-r1r17-asw-2)
                 Gig 2/2/22        152              T S   WS-C2948G 2/49
mi-za-rba-                 Gig 1/2/48        133             R S I CISCO7606 Gig 1/32
avrb-north-asw-03
                 Gig 1/2/13        129              S I   WS-C2960G Gig 0/47
avrb-north-asw-03
                 Gig 2/2/13        144              S I   WS-C2960G Gig 0/48
avrb-north-asw-04
                 Gig 1/2/14        120              S I   WS-C2960G Gig 0/47
avrb-north-asw-04
                 Gig 2/2/14        135              S I   WS-C2960G Gig 0/48
avrb-south-asw-02
                 Gig 1/2/2         154             R S I WS-C4506 Gig 2/4
avrb-south-asw-02
                 Gig 2/2/2         152             R S I WS-C4506 Gig 2/3
avrb-south-asw-01
                 Gig 2/2/1         165             R S I WS-C4510R Gig 1/4
avrb-south-asw-01
                 Gig 1/2/1         162             R S I WS-C4510R Gig 1/3
JAE1107688L(avrb-south-asw-4)
                 Gig 2/2/4         160              T S   WS-C2948G 2/50
JAE1107688L(avrb-south-asw-4)
                 Gig 1/2/4         160              T S   WS-C2948G 2/49
avrb-south-asw-07
                 Gig 1/2/26        179              S I   WS-C2960G Gig 0/47
rba-eline-mi
                 Gig 2/2/48        150              S I   ME-3400EG Gig 0/1
JAE0836V5LK(r1r17-asw-1)
                 Gig 1/2/15        141              T S   WS-C2948G 2/51
JAE0836V5LK(r1r17-asw-1)
                 Gig 2/2/16        119              T S   WS-C2948G 2/50
JAE11076881(avrb-south-asw-3)
                 Gig 2/2/3         123              T S   WS-C2948G 2/50

Device ID        Local Intrfce     Holdtme    Capability Platform Port ID
JAE11076881(avrb-south-asw-3)
                 Gig 1/2/3         123              T S   WS-C2948G 2/49
avusa-rba-ho-vois-wrl-ce
                 Gig 2/2/47        156             R S I CISCO2921 Gig 0/1
jp-r3r1-asw-01   Gig 1/2/19        165              S I   WS-C2960G Gig 0/23
jp-r3r1-asw-01   Gig 2/2/20        154              S I   WS-C2960G Gig 0/24
yourdomain.com
                 Gig 1/2/47        131             R S I CISCO2921 Gig 0/1
JAE1051HR1P(jp-r2r17-asw-01)
                 Gig 1/2/17        123              T S   WS-C2948G 2/50
JAE1051HR1P(jp-r2r17-asw-01)
                 Gig 2/2/17        144              T S   WS-C2948G 2/49
avrb-base-asw-02 Gig 2/2/23        138              S I   WS-C2960G Gig 0/47
avrb-west-asw-01 Gig 2/2/9         127             R S I WS-C4510R Gig 1/4
avrb-west-asw-01 Gig 1/2/9         177             R S I WS-C4510R Gig 1/3
avrb-west-asw-04 Gig 2/2/10        137              S I   WS-C2960G Gig 0/47
avrb-west-asw-04 Gig 1/2/10        137              S I   WS-C2960G Gig 0/48
jp-r2r17-asw-02 Gig 1/2/18        140              S I   WS-C2960G Gig 0/46
jp-r2r17-asw-02 Gig 2/2/15        139              S I   WS-C2960G Gig 0/45
r3r3-asw-01      Gig 1/2/20        160              S I   WS-C2960G Gig 0/23
r3r3-asw-01      Gig 2/2/18        172              S I   WS-C2960G Gig 0/24
av-r6r3-asw-1    Gig 2/2/25        120              S I   WS-C2960G Gig 0/24
av-r6r3-asw-1    Gig 1/2/25        170              S I   WS-C2960G Gig 0/23
CVSS1-JRO#

I hope you might have the idea of what i'm experiencing....

Jacob Gwangwa · ‎09-25-2012

As you can see from the output above. The 2960 switch can see the 6509 but the 6509 cant see the 2960.

I dont have an issue for the rest of the devices. Its only this 2960s-48ts.

i have tried the command #test cable-diagnositics tdr and its not supported.

however, i'll find out from NetPro on whether there is other ways to test the cable.

Thanks,

Jacob

Jon Marshall · ‎09-25-2012

Jacob

Can you post a "sh int status> from the 6509 for the port on the 6509 that the 2960 connects to.

Jon

Jacob Gwangwa · ‎09-25-2012

CVSS1-JRO#sh int Gig 1/2/27 status

Port Name Status Vlan Duplex Speed Type
Gi1/2/27 avrb-south-asw-8 connected trunk full 1000 1000BaseSX
CVSS1-JRO#

Jon Marshall · ‎09-25-2012

Jacob

Sorry, can you post "sh int trunk" from the 6500 for this interface.

Jon

Jacob Gwangwa · ‎09-25-2012

CVSS1-JRO#sh int g1/2/27 trunk

Port Mode Encapsulation Status Native vlan
Gi1/2/27 on 802.1q trunking 1

Port Vlans allowed on trunk
Gi1/2/27 1-4094

Port Vlans allowed and active in management domain
Gi1/2/27 1-2,4-5,8,12,16,20,24,28-29,32,36,40,44,48-49,51-52,55-56,60,62,64,68,72,76,78-80,88,91,98,100,111,188,192,196,200-201,204,208,212,216,220,224,228,230,232,234,236,400-403,545,555,800,850,915-917,995-999,1001,4094

Port Vlans in spanning tree forwarding state and not pruned
Gi1/2/27 1-2,4-5,8,12,16,20,24,28-29,32,36,40,44,48-49,51-52,55-56,60,62,64,68,72,76,78-80,88,91,98,100,111,188,192,196,200-201,204,208,212,216,220,224,228,230,232,234,236,400-403,545,555,800,850,915-917,995-999,1001,4094
CVSS1-JRO#

bharat.rajwanshi · ‎09-25-2012

Hi Jacob,

can you check is Trunk has been configured both edge properly e.g. - Interface Speed, Duplex, Encapsulation type (Dot1Q or ISL), and "sw mode trunk" command..if all are ok then it should see each other in neighbor table.

Jacob Gwangwa · ‎09-25-2012

I have servers connected to the 2960 switch and everything is working as all vlan traffic is passed through. If trunk configuration was not properly configured i would not have connectivity. For interface speed both links are set to operate at 1Gig. duplex both full.

Alessio Andreoli · ‎09-25-2012

Hi Jacob,

please these for me:

sh int g0/49 switchport

(and the relative on the 6500)

and

sh run int g0/49 switchport

(and relative on the 6500)

disabling and re-enabling cdp could help.

Thanks

Alessio

Jacob Gwangwa · ‎09-25-2012

avrb-south-asw-8#sh int g0/49 switchport
Name: Gi0/49
Switchport: Enabled
Administrative Mode: trunk
Operational Mode: trunk
Administrative Trunking Encapsulation: dot1q
Operational Trunking Encapsulation: dot1q
Negotiation of Trunking: Off
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: ALL
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
avrb-south-asw-8#

CVSS1-JRO#sh int g1/2/27 switchport
Name: Gi1/2/27
Switchport: Enabled
Administrative Mode: trunk
Operational Mode: trunk
Administrative Trunking Encapsulation: dot1q
Operational Trunking Encapsulation: dot1q
Negotiation of Trunking: On
Access Mode VLAN: 1 (default)
Trunking Native Mode VLAN: 1 (default)
Administrative Native VLAN tagging: enabled
Operational Native VLAN tagging: disabled
Voice VLAN: none
Administrative private-vlan host-association: none
Administrative private-vlan mapping: none
Operational private-vlan: none
Trunking VLANs Enabled: ALL
Pruning VLANs Enabled: 2-1001
Capture Mode Disabled
Capture VLANs Allowed: ALL

Unknown unicast blocked: disabled
Unknown multicast blocked: disabled

CVSS1-JRO#

bharat.rajwanshi · ‎09-25-2012

Hi Jacob -

can you please send the config for interfaces for both edge??

sh run int Gix/x/x

Jacob Gwangwa · ‎09-25-2012

avrb-south-asw-8#sh run int g0/49
Building configuration...

Current configuration : 119 bytes
!
interface GigabitEthernet0/49
description ***CVSS1-JRO***
switchport mode trunk
switchport nonegotiate
end

avrb-south-asw-8#

CVSS1-JRO#sh run int g1/2/27
Building configuration...

Current configuration : 201 bytes
!
interface GigabitEthernet1/2/27
description avrb-south-asw-8
switchport
switchport trunk encapsulation dot1q
switchport mode trunk
udld port
mls qos trust cos
spanning-tree portfast edge
end

CVSS1-JRO#

Alessio Andreoli · ‎09-25-2012

Remove UDLD and specify encapsulation dot1q on both the configs

interface GigabitEthernet0/49

description ***CVSS1-JRO***

switchport trunk encapsulation dot1q

switchport mode trunk

switchport nonegotiate

end

interface GigabitEthernet1/2/27
description avrb-south-asw-8
switchport
switchport trunk encapsulation dot1q
switchport mode trunk
switchport nonegotiate

mls qos trust cos
spanning-tree portfast edge ! should not this be trunk rather than edge? Consider removing this line
end

Let me know

Alessio

A core switch CANNOT see a WS-C2960S-48TS-S when i do show cdp neighbor.