Hi all. I installed Lync 2013 that is connected with the UC 500 for external calls. I am able to call in both directions. The problem is that when mobile users use clients to call internal or external (direct) numbers they cannot communicate. Also Lync monitoring shows round trip time (5176.00) and Jitter (33). Clients are connecting via edge or hdspa (3g+). 

Can you help I am quite new in this field so any input is appreciated.

I thought it is network core so I bought new switch with QoS. I will tell the results after I install it. But still any other ideas?

Thanks

If you use a full Lync client outside of the network without a VPN, can you connect the call?  Typically this would have something to do with either your A/V edge or your internal edge settings.  Can a mobile user join a conference using Lync (not the PSTN)? 

Ensure that internal zones have access to your internal edge interface on TCP/443 and UDP/3478.  Also, ensure that the edge is associated with the mediation server in your topology builder.  Finally, ensure that all the ports are open and available to your A/V edge server to/from the Internet per http://technet.microsoft.com/en-us/library/gg425891.aspx.

 

Hi Anthony, users can connect the call but sometimes I get really poor call quality, and sometimes I don't have an issue. I will start core network monitoring to see if there is a network problem. In general I didn't enable QoS for Lync. 

Any other think that can influence call quality. 

Lync FE is a collocated server based on Virtual machine ( 12GB of RAM, 8 virtual processors)

Lync Edge also a virtual machine (5GB of RAM, 1 virtual processor)

I have 2 network connections to the ISP (100/10 Mbps and 4Mbps/400kbps). I am using this second connection (slower one). But I need to mention that I will change to the faster one and than user that was tested was only one call at the time. 

Also there is a bandwidth management on the main router so that faster connection is used for everything. Basically this slower one is used as a backup line - so nobody use it.

Are there any hardware/line requirements that can contribute to the lousy call quality?

As I sad I tested 10 times and 6 times call quality was bad and 4 good. 

Any ideas?

I recon it's high time that you enable QoS on the network. And given that the call comes over 3G network, you need to ensure the network quality and strength on the device as well. often i also get such issues and turns out, it bad connection on the device causing issues. I would say it's better you make the FE server as 16 GM ram and Edge as 8 GB RAM least with dual processor. I usually assign 4 cores.

Hi, I suggest increase your Front End server Memory atleast 16GB, thought recommended is 32 GB. Also, enable Media Bypass and check the call quality. QoS enabling is necessary for controlling call quality. BR/ Baaskar R

Sorry, chiming in a bit late: "Lync FE is a collocated server based on Virtual machine "

It may be hardware, it may be network, it may be many things... but to start, I'll chime in with the others, you need more RAM.  "Collocated" concerns, me, collocated with what? 

Also, please check recommendations when deploying Lync voice on virtual servers: http://www.microsoft.com/en-us/download/details.aspx?id=41936 . Lync handles real time communications and as such is sensitive to any resource delays, make sure that the resources in your environment aren't shared and competing with other virtual servers, but are dedicated/reserved for Lync.  Also ensure that none of your resources are dynamically allocated. 

Ensure Lync Monitoring server is running and start digging into the call quality reports to see if you can spot the issue or see where it may lie, there's a lot of detail in these reports.  Even if you don't have a full SQL, you could potentially run an evaluation to temporarily help troubleshoot here.

Hi all thanks for advice. I suspected that it won't work with 12GB but unfortunately this is the max for this server. I need to buy more RAM.... So this change will wait. With collocated I meant that Mediation server is on the same machine. Features installed are Conferencing, Enterprise Voice, CAC, Monitoring. I wanted to add Chat but  I will wait until I add more memory. 

Regarding virtual machine (both host and guest). This is from the paper:

Processor

• You should disable hyperthreading on all hosts. - Can this be done in HyperV or I need to disable it globally in BIOS?
• Do not use processor oversubscription; maintain a 1:1 ratio of virtual CPU to physical CPU. -I have just one physical CPU with 4 ph cores, 7 guest machines with 15 CPU (from this 8 are allocated to Lync FE. What do you recommend? This is not 1:1 mapping. Please advice.
• Make sure your host servers support nested page tables (NPT) and extended page tables (EPT). -XEon 5530 - it says that it supports EPT.
• Disable non-uniform memory access (NUMA) spanning on the hypervisor, as this can reduce guest performance - NUMA is enabled. Do I need to shut down guest machines in order to disable it or not?

Memory

• Do not configure dynamic memory or memory overcommitment on host servers. - Memory is NOT dynamic

Network

• Use Virtual Machine Queue (VMQ) to optimize synthetic NIC performance. - Enabled
•  Use physical NIC segregation for host versus guest communications. - Not sure what is this -
• Single-root I/O virtualization (SR-IOV) is recommended. The specific configuration you should use depends on the host chipset and network adapter/driver. - Not sure what is this - 

Storage

• Use fixed or pass-through disks rather than dynamic disks. -Dynamic disc - 

Hypervisor

• Virtual machine portability or failover techniques such as live migration are not supported.

I will try to implement media bypass and to test it then. I have just 10 users so it is not heavy duty and not sure why do I need 32GB of RAM for 10 users ..... 

• Edited by MrAlexandar Thursday, January 29, 2015 2:06 PM

Hi all thanks for advice. I suspected that it won't work with 12GB but unfortunately this is the max for this server. I need to buy more RAM.... So this change will wait. With collocated I meant that Mediation server is on the same machine. Features installed are Conferencing, Enterprise Voice, CAC, Monitoring. I wanted to add Chat but  I will wait until I add more memory. 

Regarding virtual machine (both host and guest). This is from the paper:

Processor

• You should disable hyperthreading on all hosts. - Can this be done in HyperV or I need to disable it globally in BIOS?
• Do not use processor oversubscription; maintain a 1:1 ratio of virtual CPU to physical CPU. -I have just one physical CPU with 4 ph cores, 7 guest machines with 15 CPU (from this 8 are allocated to Lync FE. What do you recommend? This is not 1:1 mapping. Please advice.
• Make sure your host servers support nested page tables (NPT) and extended page tables (EPT). -XEon 5530 - it says that it supports EPT.
• Disable non-uniform memory access (NUMA) spanning on the hypervisor, as this can reduce guest performance - NUMA is enabled. Do I need to shut down guest machines in order to disable it or not?

Memory

• Do not configure dynamic memory or memory overcommitment on host servers. - Memory is NOT dynamic

Network

• Use Virtual Machine Queue (VMQ) to optimize synthetic NIC performance. - Enabled
•  Use physical NIC segregation for host versus guest communications. - Not sure what is this -
• Single-root I/O virtualization (SR-IOV) is recommended. The specific configuration you should use depends on the host chipset and network adapter/driver. - Not sure what is this - 

Storage

• Use fixed or pass-through disks rather than dynamic disks. -Dynamic disc - 

Hypervisor

• Virtual machine portability or failover techniques such as live migration are not supported.

I will try to implement media bypass and to test it then. I have just 10 users so it is not heavy duty and not sure why do I need 32GB of RAM for 10 users ..... 

• Edited by MrAlexandar Thursday, January 29, 2015 2:06 PM

Hi all, as you proposed I raised memory to 32GB for Lync FE and egde is configured with 12GB. I replaced core switch with the faster one and I've configured media bypass. As a result, when I take a look in monitoring and media quality summary, or when I place a call, I can see that quality is much better. 

I do have some jitter marked with yellow. How to improve the quality even more. I still didn't configure prioritization. Shall I do that since this is rather small company (8 users) so the traffic shouldn't be the problem. 

I'd say QoS is a way to go. Even though it's small amount of users, you wouldn't know how the network condition is. Prioritising Voice will guarantee that Voice packets comes first than any other packets.