4500 and 1231 AP issue

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Sep 18th, 2008
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I've recently migrated most of my access layer switches from 3550s to 4500s with PoE blades to accomodate new VoIP infrastructure. I've moved a 1231G AP using an injector from a 3550 to a 4500. The AP comes up and I've configured the trunk port to the AP to allow the 4 VLANs that are available on the AP. The 4500 sees the AP via CDP, but it can't seem to communicate with anything. I moved the AP back to the 3550 with the identical configuration and it works fine. What am I missing? I've attached applicable portions of the configs.

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Mark Yeates Thu, 09/18/2008 - 05:15
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The only thing i noticed is the 3550 is allowing all vlans on the trunk. The 4500 is only allowing vlans 1,12,215,216, but vlan 45 is missing from the trunk. Try adding the vlan and see if it helps.



David Niemann Thu, 09/18/2008 - 05:18
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I actually had already tried that including allowing all VLANs across the trunk. No dice. I'm just not sure why it shows up in CDP, but I can't ping the management IP assigned to VLAN 1 on the AP and the AP is not able to communicate with anything. It's almost like it's not actually trunking vlan 1 across.

Mark Yeates Thu, 09/18/2008 - 05:20
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Have you added the layer two vlans to the 4500 switch? See if the vlans are in your switch ot copy and paste below into the 4500.

conf t

vlan 12

vlan 45

vlan 215

vlan 216


jeff_groesbeck Thu, 09/18/2008 - 05:33
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Hello. Maybe you've already done this, but if you were using an injector to power the AP when you were using the 3550, did you remove the injector when you plugged it into the 4500? If they are PoE blades, you obviously wouldn't need the injector any more. You may have a problem with cdp on that port trying to negotiate power and not being able to do so. I've run into this before.



Mark Yeates Thu, 09/18/2008 - 05:40
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That's strange. All else looks fine with the switch side configs. I'm a little rusty with AP

configs these days.



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