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The place where I page to when my brain is full up of stuff about the Microsoft platform

Server 4024 part 3 – Networking

Databases are typically bound either by networking or IO and actually this can be two sides of the same coin if you are using remote storage.  So what’s new in Windows Server to improve networking both to improve access to shared storage and access to database workloads from another tier in a service or directly to your users and their applications?

So what is there in networking in Windows Server 2012 to help?

The answer is a lot and the most tangible thing is NIC teaming which is now built into the operating system this can be used both for load balancing and to provide failover, and can either use LACP (Link aggregation control protocol was 802.3ad & 802.1ax) on switches that support that or use switch independent mode.  This has several advantages over the drivers that come with NICs to provide NIC teaming:

  • It’s easy to set up and use either form server manager or PowerShell (My post on using it is here
  • You can team NICs from disparate providers  
  • You can create NIC teams inside a VM if the VM has more than one NIC.   but whatever your hypervisor you might want to do this if you have several of the new SR-IOV NICs in your hosts to provide failover as this newer NIC can’t be teamed as the network virtualisation is done on the card itself.

Note: In Hyper-V there is a per VM setting to declare which NICs will comprise a team in the VM and although I haven’t tried this on VMware but it should be fine.

If you are using SQL Server inside a VM then support for those SR-IOV NICs will improve performance, but what’s more important in my opinion is the ability to regulate network bandwidth like you can regulate CPU and Memory in SQL server with Resource Governor. Network Quality of Service (QoS) can be set on a per VM basis through Hyper-V, System Center Virtual Machine Manager or PowerShell

Then there are numerous improvements designed to improve  low latency performance to allow better remote storage access via SMB and better data centre bridging support.

Finally managing networks gets a lot easier with a comprehensive IP Address Management (IPAM) role which uses a SQL server database to manage and monitor all your subnets, DHCP scopes and IP address usage. You also get DHCP guard and Router guard option in the Hyper-V virtual switch to stop conflict occurring between applications that might actually have the same ip addresses etc. such as in a multi tenancy environment.


So that’s a quick look at SQL Server 2012 running on Windows Server 2012, but while I have been away Windows Server 2012 R2 has been announced as has SQL Server 2014. There are public betas you can download but as ever a word of caution on those – You can’t upgrade from the betas to the final products so take snapshots and backups if you want to look at those now.