Troubleshooting certificate issues in Software Defined Networking (SDN)

As you may be aware, Network Controller in Windows Server 2016 uses certificate based authentication for communicating with Hyper-V hosts and Software Load Balancer MUX virtual machines (VMs). Some SDN customers have complained about communication issues between Network Controller and hosts, although certificates were correctly configured on both the entities. On debugging, we found that… Read more

Windows network performance suffering from bad buffering

Daniel Havey, Praveen Balasubramanian Windows telemetry results have indicated that a significant number of data connections are using the SO_RCVBUF and/or the SO_SNDBUF winsock options to statically allocate TCP buffers. There are many websites that recommend setting the TCP buffers with these options in order to improve TCP performance. This is a myth. Using Winsock… Read more

Windows Networking for Kubernetes

A seismic shift is happening in the way applications are developed and deployed as we move from traditional three-tier software models running in VMs to “containerized” applications and micro-services deployed across a cluster of compute resources. Networking is a critical component in any distributed system and often requires higher-level orchestration and policy management systems to… Read more

How to find the SDN gateway local address for BGP peering in Windows Server 2016

A few days back, I wrote a blog post about some issues being faced by Software Defined Networking (SDN) customers. The issue was specific to changing VPN bandwidth settings in Windows Server 2016. You can read more about that issue and the solution here. Another area where we have seen customers struggle is finding out the… Read more

Troubleshoot Configuring SDN RAS Gateway VPN Bandwidth Settings in Virtual Machine Manager

I wanted to share some of my experiences with debugging Windows Server 2016 Software Defined Networking (SDN) related customer issues. These issues are related to SDN RAS Gateways.If you’ve deployed Software Defined Networking (SDN) in Windows Server 2016 Datacenter by using System Center Virtual Machine Manager (SCVMM), you might have encountered problems configuring the RAS Gateway… Read more

Dynamic DNS registration process can cause queue build up and failures

Hey Folks! Ajay Sarkaria here with new information on the changes in dynamic DNS registrations. In the past, we have had many customers who call Microsoft support with scenarios where dynamic DNS registration from a Microsoft DHCP server either fail or is delayed. This causes printers or other critical devices to not get registered or… Read more

Network Virtualization in the Windows Server 2016 Software Defined Networking (SDN) Stack

By Jason Messer, Senior Program Manager Using VXLAN for Encapsulation and OVSDB for Policy Distribution Windows Server 2016 is the perfect platform for building your Software-Defined Data Center (SDDC) with new layers of security and Azure-inspired innovation for hosting business applications and infrastructure. A critical piece of this SDDC is the new Software Defined Network… Read more

An Update on Windows TCP AutoTuningLevel

Daniel Havey, Praveen Balasubramanian Like all modern operating systems Windows has receive window auto-tuning to dynamically adjust the receive buffer size to the throughput and latency of the link. Disabling this feature will definitely limit your Internet speeds. Auto-tuning is consistent throughout all variants of TCP and present in all modern operating systems.   In… Read more

How to prevent accidental DNS Zone deletions in Windows Server

My name is Ajay Sarkaria and I am a Supportability Program Manager at Microsoft. We have been seeing support volumes where administrators while performing daily tasks may accidentally delete a DNS Zone which is being used in production. This post comes with inputs from our friends in Microsoft PFE team Brent Whitlow; Bryan Zink; Michael… Read more