m700 / m65 problems

[bashrael]

Hi,
we're having some troubles with a new 3cx installation.
We installed the 3cx on premise in a seperate vlan.
Fixed phones (fanvil x5) are in the same network. everything is working.

But we also need some dect phones so we bought 5 m700 base station and 10 m65 handsets Since this is a very big site with different buildings on a big terrain it's not possible to build a multicell network because the base stations are not overlapping.
What we want is to register all m65 handhelds on all basestation so a person can use his handheld when he is in range of one of the basestations.
We can provision all m700 in 3cx and assign extension to them.

First problem: when registering a handheld we can't choose what extension to assign...the handheld is always getting the first free extension.
We followed this manual https://www.3cx.com/sip-phones/manually-provision-snom-dect/
and this for handheld: https://www.3cx.com/sip-phones/register-handset-snom-m700/
The manual says to first add the extensions to the m700 in 3cx. Is this correct or should we only add extensions starting from the m700 webgui?

We tried to solve this by setting up all handhelds on 1 basestation, creating a backup and restoring this to the other base stations. This seems to be working however after a while we experience one way audio when making a call to one of the fixed fanvil phones. Audio between two dect phone stays good.
What could be causing this? Since there are all on the same vlan I think ths is not nat/sip helper issue?

Thanks for your advice!

ps. basestations and handhelds are latest firmware

 

[StefanW]

The tests are in brief

1. Provision m700 based on the guide mentioned with all the extension you like to have later on the base
2. Pair the phone to the m700 where the first device will be mapped to the first extension and then so on, you can not select the handset mapping it self
3. Once main base is up, create the multi cell setup (do not prov the slave bases). From the main guide read also: http://downloads.snom.net/documentation/M700_Multicell_Deployment_Guide.pdf and watch:

 

[bashrael]

Hi,
1. This I already did and this works.
2. ok so it's not possible to select the extension on the handheld.
3. I think I understand the multicell setup. But the if two buildings are seperated by 1000 metres of open air it's difficult to have overlapping base stations. The sites are connected by fiber.
So I guess the only possibility is to create more than 1 multicell network with different chains.
I would have been nice if all the base stations connected to the 3cx where connected as 1 network.
I understand roaming is not possible if you you don't have overlapping base stations.
Thanks!