why im getting this.

[Maykel Constantin]

I have 5 Ext on my office with the same statis ip address from comcast. and the 3cx its on an server they are all remote ext, now when i call i only get 1 or 2 that i can talk the outgoing works perfect on all ext... its showing on the 3cx console my Public ip not the local one.. i think that is the issue.. ? do i need to change on the console Extensions > Select one then > Phone Provisioning > Local SIP Port of Phone and change the ports start at 5065 keep going up? Please help Thank you.

 

[craigreilly]

The only issue should be the Local SIP Port of each phone incremented and the local audio ports (20 per set is enough). I have 4 phones in 1 office in this manner without an SBC. Some say you need to adjust the remote router as well to direct ports to each phone, but I have not had this issue.

 

[Maykel Constantin]

The only issue should be the Local SIP Port of each phone incremented and the local audio ports (20 per set is enough). I have 4 phones in 1 office in this manner without an SBC. Some say you need to adjust the remote router as well to direct ports to each phone, but I have not had this issue.

Thank you so much so i will incremented the sip and the audio ports to?

 

[Saqqara]

check out ,explains more what needs changing - it is for yealink but same applies to all phones
https://www.3cx.com/community/threa...etgear-nighthawk-x4s-d7800.54620/#post-225296

Not fimiliar for grandsteam phones , so give each phone 20 rtp ports as suggested by Craigreilly (does not state how many in 3CX documentation for the phone)

May also be down to each phone has to register the extension twice (two lines keys), as per limitations -
https://www.3cx.com/sip-phones/grandstream-gxp21-series/

 

[YiannisH_3CX]

You may also find the following tutorial useful as it explains how remote STUN phones should be configured. https://www.3cx.com/3cxacademy/videos/intermediate/configuring-remote-extensions/