Inter vlan routing

SV · December 2006

I am facing some issues while configuring a router for inter vlan routing.

I am using Boson NetSim.
Just to find where I am going wrong I have created a very simple setup.
A router connected to a switch's port#12. A pc connected to port#2 and another to port#3 of the switch.

The configurations I have done in the router and the switch is posted in :
http://www.geocities.com/shiju_v_shiju/vlan.html

The issue is that I am not able to ping the any of the sub-interfaces from the router.

The "sh ip interface brief" shows the Protocol is down for:
Ethernet0.1
Ethernet0.2
Ethernet0.3

I am not sure if I have missed some thing OR if there is a problem with the sim.

Need some help. Thanks.[/img]

keenon · December 2006

set the speed and duplex.. when this is not set on both sides it can cause issues..

also i noticed that your using a 2610 with has only an ethernet port.. which in real world "could" be used (depending on code versions) as a trunk but i would suggest changing it out to a 2620 or something with a fast ethernet port connecting to the switch

Pash · December 2006

You have to use fast ethernet ports to trunk between the router and the switch, as keenon has mentioned.

Im not sure about "real world" but when I have done this hands on with the equipment it's always fast ethernet with a straight through cat5e UTP patch cable.

SV · December 2006

Thanks a lot guys.... It works now

In 2620 it works fine with the same configuration.
In 2610 by changing the switch's trunk port's speed to 100 and duplex to "auto" things started working fine.

One main reason why I got confused in 2610 was that I was able to do the following too:
rt_2610(config)# int FastEthernet 0/0.1
rt_2610(config-subif)#

In a real router, if it does not have a FastEthernet port will this command work? Or was this just a bug in the sim?

Similarly when I type “sh ip int brief” in the rt_2610, it shows that “FastEthernet0/0.1” “FastEthernet0/0.2” and “FastEthernet0/0.3”are up now. Again why does the “FastEthernet” title appear? Is this a bug?

I really appreciated the quick help. Things are working fine now.

Webmaster · December 2006

In a real router, if it does not have a FastEthernet port will this command work?

Yes, you 'can' use subinterfaces, and trunk, on a real 2610 with a 10 mb eth int, depending on the IOS. If I remember correctly, you need at least IOS 12.1 with IP Plus. Obviously performance wise it's not a great idea, but it does work.

Inter vlan routing

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