Hello,
I am struggling with what should be a straight forward switch add to a network. We have a 2960XR three switch core stack with seven VLAN's configured, of which one is for management. The core is configured with all the SVI's for all VLANs and the second switch is only configured with an SVI for the management vlan. The second switch is a 3560CG that we are trying to use to extend the network out into the receiving area.
Both switches can see each other on layer two via cdp and show all details. The trunk is configured and up. VTP was not previously configured, but has since been configured with the core in the server role and the tiny switch as a client. I cannot get layer three to come up and all attempts to ping fail. I have wiped the 3560CG several times and started over. Where I am now is that when I run "show interface trunk" on the core I see that all VLANs appear to be being pruned on the interface to the other switch. I determine this from this section of the output:
Port Vlans in spanning tree forwarding state and not pruned
Gi2/0/35 17,19,99
Gi2/0/52 none
All other interfaces (Scrubbed from the above) are show the same as the first shown above.
The port configuration for gi2/0/52 is:
interface GigabitEthernet2/0/52
description UPLINK to warehouse gi0/10
switchport trunk allowed vlan 16-20,99
switchport trunk native vlan 16
switchport mode dynamic desirable
spanning-tree portfast network
I did not previously have dynamic desirable, it was added on a recommendation but did not resolve anything.
The corresponding port at the other end of the Trunk link is configured as follows:
interface GigabitEthernet0/10
description UPLINK to Core gi2/0/52
switchport trunk encapsulation dot1q
switchport trunk native vlan 16
switchport trunk allowed vlan 16-20,99
switchport mode dynamic desirable
The command "show interface trunk" on this switch does not show any issues. Leading me to believe the issue is at the core. The output for this switch is as follows:
sh int trunk
Port Mode Encapsulation Status Native vlan
Gi0/10 desirable 802.1q trunking 16
Port Vlans allowed on trunk
Gi0/10 16-20,99
Port Vlans allowed and active in management domain
Gi0/10 16-20,99
Port Vlans in spanning tree forwarding state and not pruned
Gi0/10 16-20,99
Core code level is: 15.2(4)E6
3560CG code is: 15.2(2)E10
I have walked away to get clear perspective, but I am still missing something that I believe is super simple. If you can offer an insight it is appreciated.
