On 13-01-14 17:38, Gianluca Cecchi wrote: I have no experience with oVirt & VoIP but here is some general feeback. This has been asked several times on the Asterisk mailing list so you might want to search those archives. If you want to use an E1 or T1 then last time I looked it's a no go because (at the time) passing on PCI(e) cards to a VM was not working very well. If you use all SIP than your mileage may vary. It all depends on how much load the box has from the other VMs. The less load on the entire box the better and the less VMs run on the box the better and the less the VoIP software does to the actual calls in transit the better. And if there's no clock skew the calls might even sound ok. Best thing you can do is setup a proof of concept and load it with hundreds or thousands of calls. Then add a few other VMs and let them do stuff that causes disk reads/writes and network send/receives (aka a lot of interrupts). Then see what happens to your calls. In general, the more calls the bigger the chance that (clusters of) bare metal boxes are used. Regards, Patrick