This documentation relates to iSymphony 3.5. You can view older documentation on the Older Documentation page

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  • iSymphony currently requires a physical system or Virtual Private Server (Such as OpenVZ, KVM, VMWare or similar) with a Network Interface Card (NIC) that supports MAC address assignment.
  • A small system that needs to handle around 5-10 concurrent users and around 200 calls per day would work sufficiently on a modern system with a 2.0+ GHz dual core CPU and 2 GB of available RAM.
  • A medium size system that needs to handle around 20-50 concurrent users and around 500 calls per day would work sufficiently on a modern system with a 3.0+ GHz dual core CPU and 2 GB of available RAM.
  • A large system that needs to handle around 50-100 concurrent users and around 1000 calls per day would work sufficiently on a modern system with a 3.0+ GHz quad core CPU and 3 GB of available RAM.
  • Utilizing a lower end CPU, like an Intel Atom, can handle a small amount of concurrent users (~5) and around 100 calls per day, but is not recommended.
  • iSymphony was built from the ground up to take advantage of multi-core CPUs. Running iSymphony on systems with only one core available is not recommended.


Please note that performance heavily depends on your dimensions and your usage pattern, much more than what is simply covered here. 
We would appreciate it if you let us know what hardware configuration works for you. Please create a ticket in our support system with your hardware specification and

Systems Over 100 Concurrent Users

We currently are aware of busy production systems with 600 or greater users, and several customers testing 2000+ users. Our internal load and regression testing is performed with up to thousands of extensions.

As mentioned in the General section above, performance depends heavily on usage pattern. It is not the number of users that may cause performance issues, but rather the things that those users and the phone system may be doing. For example, if you have 1000 users mostly idle, this should generate almost no load on iSymphony. However, if you have a complex dial plan or workflow that generates a great deal of events per second (thousands, tens of thousands), or generate complex event trees, extra care must be taken to ensure the server dimensioning and scaling is appropriate for your environment. Due to the fact that load correlates to events, it is difficult and near impossible to promote a "one-size-fits-all" specification for system requirements for systems of this size.

We work as diligently as we can with our larger customers and/or potential customers with larger systems. For systems greater than 100 concurrent users, it is highly recommended you generate a trial license from your portal and create a ticket in our support system with your desired hardware specifications. Please mention the number of users and issues in your iSymphony installation. This will allow you to test the platform in your environment before fully deploying in production. 


Occasionally, OS level kernel server tuning (such as TCP socket buffer adjustments) for high load systems may be required depending on the amount of traffic generated by the system. If you experience problems during testing with high volume or high load systems, creating a support ticket (via the link above) with the details of the issue will allow us to investigate and perhaps assist with your problems.