As Virtual Machines (VMs) are getting more powerful, we have been migrating many SQL Servers into VMs and recently after we did a initial requirement for our Veeam Backup DB server, we started to notice performance issues. On the VM, only half of the CPUs were 100% while the others were less than 20%. We checked to make sure there we have enough CPUs assigned in total 16 and even tried adjusting to make sure there was no MAXDOP hints on the queries. Even after checking these, the VM still only used the first 8 CPUs out of the 16 CPUs.
Category: Windows Server Page 1 of 2
So, here is the list of updated MP’s for Windows Server 2016, not all seems to be done but Kevin Holman has a nice list with URL’s for those that have been released so far.
Check this site for more info:
If you checked my posts before and especially LAB scenarios maybe you noticed I didn’t tag VLANs and reason is I didn’t want to complicate things and I know that some people have problem with understanding how it all works in comparison with physical switches and all. This post is meant to help clear that and I hope it will help in better understanding of Hyper-V Virtual Switch.
Network virtualization provides multiple virtual network infrastructures run on the same physical network with or without overlapping IP addresses. Each virtual network infrastructure operates as if they are the only virtual network running on the shared network infrastructure. Hyper-v Network Virtualization also decouples physical network from virtual network.
Here’s how you do it:
- Log on to the old/existing DHCP server.
- Click Start, click Run, type cmd in the Open box, right-click, and then “Run as Administrator”.
- On the Action menu, click Backup.
- Type
netsh dhcp server export C:\Users\yourusername\Desktop\dhcp.txt all
and then press ENTER.
- Install the DHCP role on the new (2016) DHCP server using Server Manager.
- Copy the exported DHCP text file to the desktop of the new DHCP server.
- Verify that the DHCP service is installed and started on the new DHCP server.
- Click Start, click Run, type cmd in the Open box, right-click, and then “Run as Administrator”.
- Type
netsh dhcp server import C:\Users\yourusername\Desktop\dhcp.txt all
and then press ENTER
- Open DHCP console on the new server.
- In the console tree, right-click DHCP.
- Select “Authorize”.
If your old DHCP server is in the same network/subnet as the new DHCP server, you’ll notice that the old DHCP server has been de-authorized automatically. This is to prevent two DHCP servers from handing out conflicting addresses.
Check to make sure that your new DHCP has all of the same settings, options, scopes, and reservations set as the current one. If done correctly, everything should have been brought over.
Easy right 🙂
This Scenario will be lot quicker and we will be using PowerShell since Nano Server is without GUI and it will definitely reflect on footprint and size of cluster.
I recommend you read Nano Server – Deployment since I will be using that procedure for creating script that will automate creation of Nano Servers.
In this scenario we will have 3 VMs and first one same as in Scenario 1 will be VM with our Domain Controler, DHCP, DNS and we will need to setup all those services on that VM(detailed info on this procedure). This time we will also need to install Failover Cluster Manager so we can manage Nano servers since they don’t have any GUI. Second and Third will be our Nano Servers that we will create with script below but before we do it we need to mount Windows Server 2016 ISO and copy NanoServer folder to our C: drive.
On Hyper V in Windows 10 we will create 4 VMs as we planned before and after VMs are created we must enable nested virtualization for our future cluster nodes.
Set-VMProcessor -VMName SRV001-A1 -ExposeVirtualizationExtensions $true
After that we need to install Windows Server 2016 and I suggest we use VM template for faster deployment as described in post earlier. Do not forget to enable MAC address spoofing in order for network packets to be routed through two virtual switches, MAC address spoofing must be enabled on the first level of virtual switch.
First VM will be our Domain Controler, DHCP, DNS and we need to setup all those services (detailed info on this procedure). Second VM will be our SAN VM and for this we will use StarWind Virtual SAN. Third and Fourth Server will be our future Hyper V host cluster nodes and for time being they must be joined to domain and given appropriate names and IP addresses.
Network interfaces on cluster nodes will be configured later with PowerShell script since I elected to team all 4 NICs using the minimum bandwidth setting for Management, Cluster, ISCSI, VM, and LiveMigration traffic. I highly recommend that you take a few moments to watch John Savill’s discussion on this method of teaming: Using NIC Teaming and a virtual switch for Windows Server 2012 host networking
Hyper Converged infrastructure is based on servers where disks are Direct-Attached Storage (DAS) connected internally or by using a JBOD tray. Each server (at least four to implement Storage Space Direct) has their own storage devices. So there are no shared disks or JBODs.
Hyper Converged infrastructure is based on known features as Failover Cluster, Cluster Shared Volume, and Storage Space. However, because storage devices are not shared between each node, we need something more to create a Clustered Storage Space with DAS devices. This is called Storage Space Direct. Below you can find the Storage Spaces Direct stack.
On network side, Storage Space Direct leverage at least 10G networks RDMA capable. This is because replications that occur though Software Storage Bus need low latency that RDMA provides.
More on this link: https://technet.microsoft.com/en-us/windows-server-docs/storage/storage-spaces/storage-spaces-direct-overview?f=255&MSPPError=-2147217396
Prior to deployment on production I wanted to test new Windows Server 2016 Hyper V Cluster. On paper it seems it didn’t change much from Windows Server 2012 R2 but still there is fear of unknown. My goal was to test all of it on my desktop workstation since it is quite good even after 3 years of service it is still capable of doing some serious business. Main new feature that will enable me to do this is called Nested Virtualization.
Well now after everything I must say I am impressed what I was capable to achieve and this will be series of articles and step by step instructions if you are interested in doing similar setup at your home or just part of it for fun.
First things comes first 🙂
In all possible scenarios planing and preparation is half work done right there, because of that we need detail plan of our future Hyper V cluster environment and all of it parts and envision our test case.
Well after quite a few deployments of new Server I noticed that Windows update will throw warring and notification “Your device is scheduled to restart outside of active hours” even do you set it not to do so – it is set do DownloadOnly.
It seems that this is a known bug in the Windows Update Settings UI in which the text does not correctly reflect the configuration of your Windows Update settings. MS Server Team will make fix soon but for now if you don’t want your server to automatically restart this is what you need to check and configure :
Validate your current Update settings using SCONFIG
To determine what updates your machine has already installed, follow these steps:
- Open a command prompt with Admin permissions.
-
Type sconfig and press Enter.
-
NOTE: There may be a short pause as the tool inspects your system.
-
-
Option #5 shows the current configuration of your Windows Update settings.
This topic aims to explain the Quorum configuration in a Failover Clustering.
What’s a Failover Cluster Quorum
A Failover Cluster Quorum configuration specifies the number of failures that a cluster can support in order to keep working. Once the threshold limit is reached, the cluster stops working. The most common failures in a cluster are nodes that stop working or nodes that can’t communicate anymore.
Imagine that quorum doesn’t exist and you have two-nodes cluster. Now there is a network problem and the two nodes can’t communicate. If there is no Quorum, what prevents both nodes to operate independently and take disks ownership on each side? This situation is called Split-Brain. Quorum exists to avoid Split-Brain and prevents corruption on disks.
The Quorum is based on a voting algorithm. Each node in the cluster has a vote. The cluster keeps working while more than half of the voters are online. This is the quorum (or the majority of votes). When there are too many of failures and not enough online voters to constitute a quorum, the cluster stop working.