Your 3CX server hardware requirements
What are the hardware requirements for 3CX? It might be astonishing but for a long time 3CX (the company) did not release specific requirements. The recommendation was "a currently sold Windows desktop will do." This might seem to be a somewhat "hazy" recommendation, but I've found that this rule of thumb actually can work quite well for a 10 to 15 extension system.
The first time I installed 3CX, I installed it on a fanless 1GHz VIA appliance PC with 512MB of RAM and a 100GB hard disk drive. I thought that, because it was a phone system, it wouldn't take many resources. Well I was wrong. When calls would come in, there was a long delay before the digital receptionist would pick up in other places when prompts played to the caller. I fiddled for quite a while before I moved the phone system to a modern desktop computer and then all the problems went away. With Asterisk, people often say you can turn an "old unused pc" into a phone system. 3CX is a Windows-based system, so make sure that you have a sufficiently powerful machine.
3CX now publishes minimum hardware requirements that appear during installation, which are as follows:
- 1GB RAM
- Pentium IV processor or higher
- Audio playback capability
Note
3CX uses an MP3 file residing on the 3CX server as the Music on Hold source. At this time, plugging an audio source into the audio card's IN port is not a feature. Also interfacing to PA systems by plugging into the audio card's OUT is not supported. We will talk more about PA system integration in Chapter 8.
Obviously, if you are running 3CX alongside an Exchange Server, Active Directory, and File Sharing on a Microsoft Windows Small Business Server, you will need a more powerful machine. 3CX has published a test in such a situation on their official 3CX blog at http://www.3cx.com/blog/voip-howto/ no-dedicated-server-needed/.
For the test, the server was configured as follows:
- Intel Core 2 Duo E4500 2.20GHz
- 4GB RAM
- 50GB SATA hard disk drive
- 100MBps network connection
In the test, Windows Small Business Server was running IIS, Exchange Server, and Active Directory. 3CX was installed using the Cassini web server option. A load equal to 25 users heavily using Exchange Server was put on the server. Now a 16 simultaneous calls load was put on 3CX. In one hour, 2,000 calls were made. During this test for all 3CX services, the CPU usage was at less than 15%. The 3CX memory usage was approximately 300MB with Cassini using about 100MB. Exchange Server did not use more than 10% of CPU with a total CPU usage of about 30%.