QOS issues

[hherd]

We are using Hyper-V with Windows Server 2008 R2 and 4Gb of memory and 4 procs assigned to the 3cx server

Currently our gateway is the Smartnode 4960


Our legacy PBX is a Nortel ICS, it currently has roughly 60 users on it

The 3cx system VM has 7 users on it currently running Yealink and Cisco 504G phones.
-Qos has been applied on all voice ports on Cisco 3750X switches along with QOS being applied to trunk links
-The Smartnode is being used as the gateway for all traffic coming in and out of both systems for voice


My issues are

-calls from PSTN are hearing a static sound (almost like a squelch from a CB radio)
-on-premise 3cx users will hear alot of break up on the other end when on a call with multiple callers (confernence call)
-there is intermittent echo at times but not as predominant as the static


My questions:

1. Should the server be running on a physical is that causing some of these issues we are seeing?
2. Could the Smartnode be causing the majority of these problems since we are not seeing any of these issues with internal calls
3. we are using the Yeahlink T22 phones is there any special configuration that needs to be done on my switch ports since they are not cisco phones and the switches are cisco switches

 

[netswork]

I am running 3cx as a VM with no issues, but on vmware.

You have to be careful in a virtual enviroment when giving a server more than one vCpu. How many vm's do you have running on the hyper-v server? Do you have enough CPU cores that there will never be contension with 4 procs assigned to 3cx? If you have 4 proc's assigned to 3cx and only 3 CPU cores are available at any given moment, the VM will wait for the 4th core to be available before processing commands. You can actually hurt performance in VM's by assigning multiple vCpu's.

How is your QOS configured? The cisco phones will tag its traffic with with a DSCP value, I dont know about the yealink phones.

Are these phones on the same LAN?

Are you using analog lines with the patton?

 

[SY]

VMs do not extend performance of the host. They just help to organize usage of the host power.
With proper tuning, 60 calls can be handled even by Atom Z501 processor...

 

[wagner.damiao]

1. Should the server be running on a physical is that causing some of these issues we are seeing?

keep in mind If the server is a physical or virtualized, does not degrade the connection between the phones. The quality of call is directly related with the bandwidth avaliable to upload and download.

2. Could the Smartnode be causing the majority of these problems since we are not seeing any of these issues with internal calls

We have evaluate the conditions of internal and external calls, for answer this question.

3. we are using the Yeahlink T22 phones is there any special configuration that needs to be done on my switch ports since they are not cisco phones and the switches are cisco switches

Yes, you can use QoS, tagging the packets.

Best Regards!