Meraki MR42e management IP via DHCP not working

[Mamba123]

hi Guys
I have a problem.

I got a new MR33 and 4 new MR42e APs and should set them up.

The APs are connected to a Cisco 2960 switch, switch port is configured as a trunk with Native VLAN 555.

VLAN555 also assigns the IP address and comes on the Internet.

An MR33 works without problems, it gets the correct IP from the VLAN555 and is immediately visible in the dashboard. Everything OK.

But not a single MR42e gets an IP address. Why not? What is different with an MR43e than with MR33?

I also cannot access the local page on the MR42e. The way it is described on the Meraiki page does not work.

Can anyone help here?

Best regards

Mamba

[Network-dad]

Are the MR42e's getting POE? Have you confirmed they are powering on? what is the status light?

[Mamba123]

Hi, yes PoE is enabled. LED status is blue.

[rhbirkelund]

Adding to @Network-dad, the MR33 is a 802.3af (normal PoE) AP, whereas MR42E requires 802.3at (PoE+).

If the MR42E is only getting .3af, it will power up in low power mode, meaning Air Marshall is disabled, as well as two out of three streams. For your reference, it's noted in the installation guide.

Edit: Ninja'ed by @Network-dad himself. 😉

[Network-dad]

Your MR42E is equipped with a multi-color LED light on the front of the unit to convey information about system functionality and performance:

• Orange - AP is booting (permanent Orange suggests hardware issue)
• Rainbow - AP is initializing/scanning
• Blinking Blue - AP is upgrading
• Green - AP in Gateway mode with no clients
• Blue - AP in Gateway mode with clients 
• Blinking Orange - AP can't find uplink 

[Mamba123]

hi Guys
first of all thank you for quick answers.

A few more details:

1. I also tried it with a power injector. Exactly the same behavior.

2. The LED lights up blue.

3. AP is shown in the dashboard as a repeater because it does not get an IP.

If AP got too little power, I would understand that the antennas stay off, but why doesn't it get IP.

[rhbirkelund]

Have you checked that the DHCP pool is not exhausted?

Verified switchport configuration on the catalyst switch?

[Network-dad · Accepted solution]

do you have the vlan set on each ap?

If not reboot the ap after setting it...

[Mamba123]

Hi,

VLAN was not entered. As I said, MR33 works perfectly on the switch and gets the IP address from the DHCP server.

Yes, DHCP Scope is big enough. I tried two things. One external DHCP server and one DHCP on the switch.

in both cases MR33 works fine and MR42 does not.

I have 4x MR42 and the same problem with all of them. All APs are new and have been supplied by Cisco.

The only difference is the power consumption.

I'll test it in the company tomorrow morning and give you feedback.

AP may not get enough power and cannot boot properly.

[LuisCruz]

Leaving the VLAN field blank means that the AP will try to get an IP from the native VLAN DHCP scope (VLAN555 in your case). Try changing the native VLAN on the 2960 to something else, then set the VLAN field on the AP to 555, this way the AP will try to get an IP from tagged VLAN 555 scope.

This would be some strange behavior, but at least we will get some info to have a case open.

[Network-dad]

My guess the Cisco 2960 may not have the proper POE of the MR42e's... Cisco 2960 specs here

the MR42e requires "Power over Ethernet: 37-57 V (802.3at required; functionality-restricted 802.3af mode supported)" MR42e's specs here...The Cisco is  IEEE 802.3af-compliant but that mean the MR42e is operating in functionality-restricted mode... Also depending on the model of 2960 not all ports provide POE. The Cisco Catalyst 2960PD-8TT-L Switch only has 8 ports of POE have you tried plugging it into a different type of switch?