This might occur when multiple meetings with high number of participants is initiated the Skype for Business pool is unable to process this request.
We can also see the following logs recorded in the FE servers also:
Log Name: SFB Server
Source: LS ApplicationSharing Conferencing Server
Event ID: 32032
Task Category: (1304)
Internal Application Sharing Server health monitoring has detected that Application Sharing Server is running at a moderate capacity.
Application Sharing Server Health State: Loaded
Cause: Application Sharing Server has reach moderate capacity.
This application sharing parameter is controlled by MaxBandwidthPerAppSharingServiceMb
What is MaxBandwidthPerAppSharingServiceMb parameter used for ?
This value Indicates the maximum amount of bandwidth (in megabytes) set aside(allocated) for the Application Sharing Conferencing service.
MaxBandwidthPerAppSharingServiceMb can be set to any integer value between 50 and 100000, inclusive. The default value is 375 megabytes.
This setting is applied and restricted to share the bandwidth within the pool at the org level and not in the server level.
Changing this value cannot be scoped only on specific servers.
Solution for this problem:
Look for the value MaxBandwidthPerAppSharingServiceMb.
The default value is 375 MB . Increase them to some extra value and see the results.
The value can be increased by running the below command:
Set-CsConferencingConfiguration -Identity conferencingconfigurationname -MaxBandwidthPerAppSharingServiceMb “MBSizeValue”
But the strange thing is really hard to identify this actual consumed value from the default 375MB which should be sufficient for a conferencing type for the Application sharing like a powerpoint in the presentation using Remote Desktop Protocol (RDP) protocol.
Whenever a meeting is schedule in Skype for Business server will create an entry in the Conferencing database but it will not reserve any memory in prior for the meeting which is going to occur in future. It will use the built in load balancing logic which will dynamically/instantly allocate conferencing resources on the FE servers based on the load on all FE servers and number of meeting that is occurring at the moment.
So here the value is exceeding because the pool is already running at its peak threshold level of its allocated capacity.May be if more meeting is initiated with more than 300 participants the Pool might run out of resource and this issue might occur.
The Conferencing CDR tables has the below records:
Conferences table in Skype for Business Server 2015:
Stores information about all conferences that were archived or whose details were recorded, including ConferenceURI, and start and end time.
ConferenceSessionDetails table in Skype for Business Server 2015:
Stores information about every SIP-based conference session, including start and end time, user ID, response code, and diagnostic ID for each session.
FocusJoinsAndLeaves table in Skype for Business Server 2015:
Stores information about conference joins and leaves, including users’ role and client version.
McuJoinsAndLeaves table in Skype for Business Server 2015:
Stores information about the A/V Conferencing Servers that are involved in a conference and the user join and leave times.
If the organization requires meetings with greater than 250 participants, we need to plan for a dedicated pool to support the load
We can use the capacity planning conferencing for meeting – https://technet.microsoft.com/EN-US/library/mt297718.aspx
Thanks & Regards