Just playing around basically but I've setup a router for use with intervlan routing.
fa0/0 fa0/0.2 fa0/0.3 - all in different subnets
dot1q 2 and dot1q 3 configured on the 2 sub interfaces
on the switch (2950) fa0/12 is the trunk link. - switchport mode trunk
setup vlan 2 and vlan 3 and added fa0/2 to vlan 2 and fa0/3 to vlan 3
Now pc's in vlan 3 can ping pc's in vlan 2 and the other way around. However neither of them can ping the pc in vlan 1 which is hanging off fa0/1
Is this how its supposed to work? should I be able to ping devices in Vlan 1 with this kind of setup or not? If so where have I gone wrong. FYI I havn't setup a ip address for vlan 1 or gateway on the actual switch. But that shouldn't matter I'm guessing.
interface fastethernet 0/0.2
encapstulation dot1q 2
ip address 220.127.116.11 255.255.255.0
interface fastethernte 0/0.3
encapsulation dot1q 3
ip address 18.104.22.168 255.255.255.0
So, int the switch you have switchport configured as belongs to vlan 1, 2 and 3, and the pcs in each vlan o each port, must point to the ip address of the subinterface of the router as the default gateway.
the same applies for isl.
Make sure vlan 1 is in the allowed vlan list on the switch:
switchport trunk allowed vlan 1-3
and make sure vlan 1 is the native vlan:
switchport trunk native vlan 1
then it should work as expected.
Ta I'll give that go when I get home.
havohej, my understandiing of it is that because I'm using 802.1q then the management vlan, vlan 1 is not required to be on a sub interface. I think thats only required when using ISL.
So basically fa0/0 has ip address 192.168.1.1, and the two sub interfaces have 2.1 and 3.1 respectively. All vlans are using the 3 interfaces as their gateways etc etc.
On the subject of a router on a stick set-up, what would be the best way to set-up the interface? Assuming you have one ethernet interface for the LAN and one serial for the WAN, and you have a few class c address spaces. Would you use subinterfaces on the ethernet interface or secondary addresses? I'm curious about opinions for this type of design.