A dumb question, but here goes

If the machine FreePBX was running on had unlimited CPU power and hard drive space, is there a limit to the number of phones the system could have connected to it?

Just wondering.


Not intrinsically, by default there is a limit in your system’s ulimit settings, and there is a pragmatic limit in your network’s bandwidth utilization. For huge implementations however, most would argue that you should delegate your VOIP sessions to a better designed proxy.

Much study by Digium has been done on this subject. Google, Asterisk load testing and Asterisk dimensioning for a ton of info.

As Dicko pointed out, Asterisk is an incredible voice application development platform, so if you are looking to build a huge IVR, it’s your ticket. If you are looking to provide Class 4 or 5 switching you really need a softswitch that has better SIP manners.

Thanks for the answers guys. Dicko you mentioned ulimit, never heard of it. But basically if I am wondering if there is a limit (depending on the PC) to how many devices I can connect. In other words licensing of any kind. I have not found any references to such. I just don’t want to have a gotcha somewhere down the line.

There is no licensing limits in the opensource parts of FreePBX there are however some limitations in mysql and mp3 if you deploy a commercial system., you will need to learn about ulimits if you deploy large servers, google can help you there, it is not about the services you provide, it is about how needy they are by thread.

Thanks Dicko I will look ulimits up. I am going to deploy Freepbx commercially, just looking to see if there are any hidden limits.


Just out of curiosity how many SIP peers are you planning for?

No number in particular. I am just thinking out loud. If I had a server grade system could I get 250 peers on it?

250 is easily achieved with very average specs.

You could easily support 250 concurrent g.729 trascoding sessions on a modern dual quad core xeon.

You do realize that FreePBX is not designed as a trunking server or a shared tenant PBX? It is missing key features for reselling such as CALEA and e911 management.

I am just wondering is all. I was thinking of a large deployment of a company in a single campus or building. Thanks for the answer to my noob questions.