Just a minute while I prepare your answer.
To verify inter-vlan routing use the following commands:
"#show ip interface brief" to verify correct IP settings on interfaces"#show ip route" to check the routing table to make sure the devices know the routes to each vlan"ping x.x.x.x" ping all gateways for each vlan to verify communication passes through. You can also ping devices on each VLAN
The biggest pitfall to router-on-a-stick design is the fact that you have one single point of failure. If that router fails, there will be no inter-vlanrouting. All VLANs will have become isolated and cannot communicate to services beyond it's subnet. Also, the link between the switch may become a bottleneck in the network as more data from the VLANs come through than the link can handle. Another possible disadvante is that it consumes a lot of resources on one device (the router) possibly more than it can handle.