Application Notes for Avaya IP Office Release 8.1 and Avaya Session Border Controller for Enterprise 6.2, with AT&T IP Flexi
![Avaya IX Workplace Help - SIP Registrar FQDN must be set and must be reachable from external address - Avaya: IP Office - Tek-Tips Avaya IX Workplace Help - SIP Registrar FQDN must be set and must be reachable from external address - Avaya: IP Office - Tek-Tips](https://res.cloudinary.com/engineering-com/image/upload/v1594597830/tips/FQDN_uydniv.png)
Avaya IX Workplace Help - SIP Registrar FQDN must be set and must be reachable from external address - Avaya: IP Office - Tek-Tips
![Avaya IX Workplace Help - SIP Registrar FQDN must be set and must be reachable from external address - Avaya: IP Office - Tek-Tips Avaya IX Workplace Help - SIP Registrar FQDN must be set and must be reachable from external address - Avaya: IP Office - Tek-Tips](https://res.cloudinary.com/engineering-com/image/upload/v1600186349/tips/222_ny4gf1.jpg)