Assistance Required - Creating VLANS and adding to Routing Table

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Aug 2nd, 2010
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Hi all,

I'm in the process of creating a new VLAN and would like to know how I could get this added to the Routing table?

Basically I have a Nework Range that is variably subnetted into 6 Subnets. The Network that is variably subnetted is

Looking at the Routing table, it advises below:

C           172.30.x.x/24 is directly connected, VLANxx

Now my question is when I create my new VLAN, which will be in the same Network, how do I get it added to the Routing table? Also how would I be able to see that the 172.30.x.x/16 Network is variably subnetted into 7 Subnets after creating my new VLAN?

Any assistance will be much appreciated.

Many thanks

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Jon Marshall Mon, 08/02/2010 - 07:56
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If you are using a L3 switch then you would -

switch(config)# int vlan 10

switch(config-if)# ip address 172.30.x.x

switch(config-if)# no shut

where 172.30.x.x is not the same as the vlan already showing in your routing table.

You should then see the new entry in the routing table.

No idea what you mean about the 7 subnets ?  it is up to you to subnet them down so unless you do and add them to the device it won't magically happen for you.


Nagaraja Thanthry Mon, 08/02/2010 - 08:12
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Adding the new subnet to the routing process depends upon the routing

protocol you are using. If you are using RIP/IGRP, then it will be

automatically included. If you are using OSPF/EIGRP, then you might have to

add a specific statement. On the switch where you are adding these, you will

see all seven subnets.

Hope this helps.




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