Quodro 2x to be remote extensin off 16x

[baoan]

Hello every one,

can anybody help me to setup the 2x system to be remote off the 16x system, here it's the description off 2 systems:


16X:

- Have a DSL connection with Public IP address (Static)
- Full CONE NAT
- Have one VE (Virtual Extension) for the 2x
- Have 4 PSTN lines


2x :
- Right now have a Wireless Connection (Portable Internet Connection) from Rogers by next week will have a T1 with Public IP
- Has no PSTN Line
- Have 2 extensions
- FULL CONE NAT

Tee phones behind those two systems work well between them (Extension to Extension).

The problem it's, when i try to call from 2x to a PSTN phone (My cell), i got a message said "CHECK YOUR EXTERNAL PHONE LINE"


Thank's

[davrays]

Hello

you get the "CHECK YOUR EXTERNAL PHONE LINE" because there is no PSTN liune connected to the 2x. Thats natural.
I guess, you want to be ablet to call from 2x extension via the PSTN line connected to the 16x, right?
If thats right, you don't need to setup remote extension for that. This has two drawbacks:
1. You cannot use Virtual extension on 16x as a remote extension for your 2x. You have to use extension attached to a line - either IP Line or FXS line. If you register 2x extension as remote on 16x, you lose one line on 16x.
2. If your 16x is behind NAT, you will have big problems connecting remote extension to that. Depending on your NAT/router, you will most probably need to setup a static port mapping for SIP and RTP ports, and even in that case I am not sure you'll not have other problems. Remote extension should be registered on a Quadro, which is NOT behind NAT (remote extension itself CAN be behind NAT, but Quadro shouldn't).

But if your goal is to use PSTN line of 16x from the 2x extension, there is a much easier way to go:
you need just to add two routing rules. One rule on 2x (for example with pattern "9*" withou NDS), which will route calls to the 16x address, and another rule on 16x (with pattern "9*", NDS=1) which will route those calls to PSTN.

Just don't forget to secure the connection between those Quadros, either via VPN or "SIP Access" rule, otherwise other people will be able to call via your PSTN line.