Today we are announcing the latest set of Cumulative Updates for Exchange Server 2016 and Exchange Server 2013. In addition to normal fixes to customer reported issues, these releases also include...
Updated Jul 01, 2019
Version 2.0
Blog Post
With the support of .NET Framework v4.6.1, is it supported to enable the PortReuseOnSocketBind network optimization that was introduced in .NET 4.6 ? Since Exchange seems to target v4.5, sockets created in the HttpProxy probably don't make use of this. However, this can be enabled globally on the server by setting HWRPortReuseOnSocketBind in the registry. I've faced a port exhaustion issue in the past with Mapi/HTTP where sudden bad network conditions (datacenter links dropping randomly in a full Active/Active infrastructure (following the Unbound model)) were causing port exhaustion because sockets were not freed fast enough + not reused. Rare conditions, I have to admit but thinking of enabling this optimization could be beneficial... for both stability and scalability of large Exchange environments.
Now that this is not documented at all for Exchange, it is likely not supported.
Any plans to look at using this scalability feature in the future ?
As you suspected, we are still targeting 4.5.2 compatibility. We have not yet taken any hard dependencies on 4.6.1 features. You can expect that at some point in the future though. We are looking at port re-use provided by the OS with Exchange Server but don't support this at the moment.