I’ve just upgraded my home NAS from OMV3 to OMV4 (Debian Jessie to Debian Stretch) via the OMV ISO - and took the opportunity to upgrade Asterisk15 to Asterisk16 (downloaded src and compiled) and FreePBX 13 to FreePBX 14.
FreePBX wants php5.6, and OMV/Debian 9 want php7.0 - but OMV uses nginx whereas FreePBX uses apache2 - so I managed to get everything to play nicely.
All open source components (commercial stuff isn’t supported debian) should work without issue in PHP 7. PHP 5.6 is a minimum. If you find an issue with FreePBX+ PHP 7 please report it to https://issues.freepbx.org
Anecdotally, I just put up a Debian 9 /FreePBX 15 system, to get UCP working I needed to install php5.6 and set apache2 to use it, then download/icu-devel and icu Centos 7 rpm packages and use alien/dpkg -i on each one as FreePBX doesn’t like the Debian available ones. So far so good . . .
Several freepbx php scripts (including fwconsole) fail under php7.0 for me with:
root@MediaVault:/var/www/html/ucp/assets/js/compiled/modules# php7.0 /usr/sbin/fwconsole
Whoops\Exception\ErrorException: Methods with the same name as their class will not be constructors in a future version of PHP; dayNightObject has a deprecated constructor in file /var/www/html/admin/modules/daynight/functions.inc.php on line 9
Stack trace: