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VLAN, What am I missing?

Cisco IOS Software, C1700 Software (C1700-K9O3SV8Y7-M), Version 12.4(7), RELEASE SOFTWARE (fc6)

(2) Cisco Catalyst 1900/2820 Enterprise Edition Software Version V9.00.07

I cannot get any port on switch #2 to pull an IP address from the routers SHCP VoIP pool. Trunking is enable on both routers, sh cdp neighbors detail command on bith switches display each hardware's MAC address. The router discovers all other MAC address's except switch 2.

The router is connected to switch port 1, switch 1 port A (trunk) connected to switch 2 port A.

What am I missing in my configuration?


Re: VLAN, What am I missing?

Hi Friend,

Lets check the basic connectivity first. Can you assign a static IP address on any machine on switch 2 and try to ping the router subinterface for voice and data subnet. This will make things clear as machines are able to reach router from switch 2 or not.

Then later we can check the trunk status and other stuff depending upon the results of ping.

Also because router itself is a DHCP server you do not need any "ip helper-address" command on the subinterface of the router.



Community Member

Re: VLAN, What am I missing?

Router Fasteth0/0.1 IP

Router Fasteth0/0.2 IP

Switch #1 IP

Switch #2 IP

Switch #1 connects to switch #2 via Trunk port A.

router#> sh cdp neighbors detail

on router #1 displays the MAC/IP of switch #2

Connected a laptop to switch #2, assigned IP, I am able to ping switch #2 ( to ping switch #1 from switch #2

Both switches have Trunking and STP enable. If I create VLAN 2 on switch #2 ( ICMP request fail from the laptop (

Any thought's?

Re: VLAN, What am I missing?


What is the gateway in switch#1.And what is the management vlan on u r switches.

from u r config it seems that for siwtch#1 management vlan is VLAN#1 and for Switch#2 management vlan is VLAN#2.

they are in different they need a gateway.configure the default gateways in u r switches and try.



Community Member

Re: VLAN, What am I missing?

Yes, each switch does have a gateway configured.

Switch # 1 (also on router int fe0/0.1)

Switch # 2 (also on router int fe0/0.2)

Community Member

Re: VLAN, What am I missing?

If you config on your router is correct you have created VLAN 100 and VLAN 200. You also have changed the native VLAN to 100. You will need to make sure you change natvie VLANS and your switches.

Try creating an access vlan of 200 on you switch connected to the router and see if that works. If so try making the access vlans of 200 on you furthes switch.

Hope this helps

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