WM3400 v5.5.5.0 causing IP conflict

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So I just updated 24 locations using the WM3400 controller, of which 4 had a strange issue arise. I updated the devices and rebooted them, only to lose access to the network causing me to go onsite to find out what the issue was.  When on site I would attempt to access my firewall, lets call it, only for the Extreme login page to pop up.  I found this odd as I could also access the controller using its normal assigned IP address, lets call it  Accessing the normal page (.15) I could find nothing odd, so I went ahead and signed into the .1 address.  Apparently the controller created another virtual interface allowing me to configure it.  I did a bit of navigating, found the VLAN 1 interface and had to disable DHCP which promptly fixed the network issue.

I'm curious why this is happening and how I can prevent it from happening again. (I rebooted the device yesterday and it occurred again) It seems strange that a firmware update would cause the devices to enable DHCP and create IP conflicts with my firewall.  Also as a side note, these particular devices  (4 out of the 24) will not allow me to ping them now, even though I created a static route for them. 
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Sean Tutor

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Posted 3 years ago

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Colatuno, Joe, Escalation Support Engineer

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Hey Sean,

I assume you are getting the controller GUI login page and not a captive portal page correct? 

What version did you come from? 

Who is handing out DHCP? 

When you disable dhcp are you committing and saving the changes? 
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Brandon Clay, Escalation Support Engineer

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Hi Sean,

I've got a few questions to get a better idea of what happened.

When you say the Extreme login page, is this the login page for the web interface of the WM? Or is it a captive portal page?

Is the normal IP address ( on vlan 1, or is it on another vlan? 

What is the DHCP server in this network? Generally, I wouldn't expect it to hand out the firewall's IP as a lease.

Also, are there two controllers clustered, or just a single controller?

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Sean Tutor

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Sorry for the late reply, had to go on site to poke and prod.  Quick reply to your questions:

Just the login page for the WM - which was apparently an access point and not the wireless controller


The DHCP server was the problem, which I'll explain below.

And just a single controller.

So it would appear whoever setup the DHCP on our firewall used the IP address of the gateway and only the gateway on these 4 devices that were having issues.  So that explains why the devices are pulling a conflicting IP.  What is odd is that this issue is just now occurring.   The devices pulling the IP are the access point, which explains a little bit. However now, when I look up the access points IPs (after having changed the DHCP range) they come up as instead of a proper IP like (Using the GUI) 

I suppose this closes the main issue for now.  Now I just need to find out how to change the access points IP from
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Drew C., Community Manager

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Hi Sean, I've marked this thread as "Solved."  If that's not the case, let us know how we can help!