Very basic help question

[martintim]

Hi there

I am working for a company who use a VOIP system with an external company hosting the 3CX part of it - it all works fine but I am yet to see how it is all set up.

My very basic question is if we get an emergency Router with a SIM card can it be simply used to keep the few phone numbers the company uses going if our main internet provider has an outage? The main point is (however it is set up) if we swap the phones over to the secondary Internet Provider's router will the dedicated numbers remain - will the phones just continue to work as they don't care where the internet signal is being picked up?

Apologies for the very basic question I am just starting to try and understand how it all works.

Many thanks for any help.

 

[Alphabetic]

At your site there is probably an SBC set up that routes the traffic back to the PBX in the cloud.

the SBC must be able to get out on the internet to talk to the PBX.

if your internet dies, the connection between SBC and PBX dies.

your 2nd internet connection (router) will need to have the same IP that the SBC uses for its gateway so the internet can be restored without having to set up or reconfigure your SBC/phones - This wouldnt be a problem if you have 1 router with 2 WAN connections.

Now, if youre going to be using a router with a SIM, you may as well ask staff to use their 3CX mobile app to make/receive calls.

But, you could also configure your emergency router to be the same IP as the one that's gone down and then you'll be back up and running.

Note, SBC may need a restart to start using new WAN.

If the phones are set up for STUN then this is a different ball game that will require firewall rules etc and if you're introducting a new NAT box and WAN you may find a) limitations b) WAN provider doesnt allow port forwarding

This is a question you need to put to your 3CX provider and ask them for a disaster recovery plan.

 

[NikosT_3CX]

@martintim as @kieferschild said the main thing here is how to route the traffic out
Now if your intetnal default gateway 's next hop is the router/firewall that failed then all will fail.
If there is a possibility to setup a route map with a ping SLA on your intenral default gateway and then if the main router fails to route traffic to the secondary router you have, then you wont have any issues as the SBC will re-establish the connection with the PBX.

 

[leejor]

You might also check to see if the provider that you plan to get the SIM card from, will assign your router a public, or private IP.