Routing – Successful Intervlan Routing on a Layer 3 Switch, Unsuccessful IP Routing

You seem to be missing the ip routing command which enables L3 routing on the switch.

To allow VLAN routing four things are neccessary:

• The VLANs you want to route must exist on all switches.
• The VLANs must be allowed on the trunk between the switches.
• Interface IPs for each VLAN must be assigned.
• IP routing enabled.

In your case you need to add the following lines to your config:

Switch7:

Switch(config)#vlan 20
Switch(config-vlan)#name PC2
Switch(config-vlan)#exit

Switch8:

Switch(config)#vlan 10
Switch(config-vlan)#name forPC1
Switch(config-vlan)#exit

It is not neccessary to have the same names of the VLANs on both switches but it's a good practice to keep in consistent.

To verify that the VLANs are created on both switches you can issue the following command from Privileged EXEC:

Switch#show vlan brief

and it should list both VLAN 10 and VLAN 20.

Regarding the other condition it should be said that the default is to allow all vlans on the trunk, but to verify that it is indeed allowed you can issue the command:

Switch#show interfaces fastEthernet 0/1 trunk

and you should see vlan 10 and 20 listed under "Vlans allowed and active in management domain" aswell as "Vlans in spanning tree forwarding state and not pruned". If it is not listed under the latter one you need to check your spanning-tree configuration but that should not be a problem in this case.