FreePBX discovery and connection will not work after changing phone IPs


I have a FreePBX server with about 25 Digium phones.

Yesterday, we proceeded to map the mac address in the DHCP server and made IP reservation for all phones to be in the 10.0.7.XXX range

Once the phones refreshed their DHCP lease, about 30% of them won’t reconnect to FreePBX.

For example, I have a D70 in my office.


Normally, the phone would start, then discover by itself the FreePBX server, and then I would just need to choose my extension.

Now, it will not find the FreePBX server, and also, if I input it’s IP manually, it will not connect to it.

Any idea?

So your phones are on, what is the IP of your server? Your router?

This sounds like it might be a netmask issue ( might need to be or something)

Thanks for your reply

Yes, this was my first thought.

However, my router is a pfSense server and the netmask of the network is

The FreePBX server is in the 10.0.3.XXX range

All Digium phons are now in the 10.0.7.XXX range

Finally DHCP gives leases in the 10.0.1.XXX, this is where all the phones were previously

Concerning FreePBX or the “Digium Phones” app I’ve been trying to find relevant settings but I can’t find any.

Also, some phones had no problem connecting, which I don’t understand why…

Additional notes, we also have 10 Polycom SoundPoint IP 331 which are now also in the 10.0.7.XXX range and have no problem connecting with FreePBX.

The real problem is that when a phone restarts from factory default, it will not auto discover the Digium Phones configuration server, nor will it connect to it if we input the info manually.

I’ve tried everything and at this point I don’t know what to do.

Any help would be greatly appreciated.

Can you access the Web UI of the problem phones from your PC?


For now I took the 12 phones which mysteriously didn’t work and removed the DHCP reservation

Now they have an IP in the 10.0.1.XXX range and resetting to factory default made them work again

I don’t know what the hell is going on… but I had to make it work so for now it’s like that

If you have any idea I’ll test it with my personne phone so I don’t mess with the others.

My phone (a D70) was one of those which had problems…

Sounds like a NAT rule almost…

What if you set the IP statically on the phone instead of using a DHCP lease? (generally recommended anyway)?

What if you take the IP of a working phone and give it to a non-working phone? Does the problem follow the IP or does it follow the device?

Are they all using the same firmware version?

Firmware is set with DPMA to the latest (firmware_1_4_2_0_package)

All phones are configured to download latest firmware

DPMA version is 2.1.1 (latest)

But anyway the problem is not at the firmware level, since they can’t even connect or find the configuration server.

Something very weird is going on, my instinct tells me it has to do with network but I don’t see how…

These things will be key to solving this problem.

Update on this:

So all the digium phones started acting up one after the other so I had to delete all the DHCP reservations and all is back to normal.

Now this is not a DHCP reservation issue, simply because we also have POLYCOM IP331 phones for which I did the exact same thing (get their mac address and make a DCHP reservation) and they kept working until their initial lease expired, then got their new IP in the 10.0.7.XXX range and didn’t even stop working in between.

So I think I can safely assess that this is a problem with DPMA.

Once the phones get DHCP reservation, they do not see the configuration server.

Or sometimes, after hitting refresh several times, they will see it, but connecting to the server will time out.

So I’d like to have help on this issue please.

Say a working PCOM phone is and a bad DP is

Does the PCOM still work a if you put it on 42 and does 69 fix the DP?
Does a static IP on the DP in the range fix the issue?

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So I think I can safely assess that this is a problem with DPMA.

Is that because you saw MESSAGE packets received by Asterisk?
Were response packets not going out?
Were response packets going out to the wrong address?

If you didn’t see MESSAGE packets received by Asterisk, did you see the phone sending them to what would have been the proper address?

Sorry malcolmd, I didn’t mean any offense

DPMA is a extraordinary module and it works great

Now I’ve tried a LOT of different things and the error was nor in my network, nor in DPMA

The problem came from fail2ban on the FreePBX server.

It appears that if you change the IP of a server that’s already registered with DPMA, when the lease expires and it’s getting it’s new IP, the new IP will get banned.

The workaround I found is the following:

  1. Set the new IP in the DHCP reservation

  2. Reset the phone to factory setting

Then everything works.

Thanks guys for your replies

I know this is an old thread but I had the same problem with Astra and Vertical phones. The issue was the TFTP server was not set to the PBX box in pfSense. Adding that in to the pfSense DHCP server setting and applying the changes seemed to fix things. It is weird it only happened to some of the phones and only some of the times since the pfSense has been in place for over 3 years like this.