Small scripts to configure Livemigration on Hyper-V Hosts & Cluster

Hi everybody,

based on blogposts by John Savill and Ben Armstrong I developed two small scripts to configure Livemigration on Hyper-V Hosts and Cluster to save some time for configuration. I will no provide my whole script but I think the two snipes will help you too 🙂

First one you run on all Hyper-V Hosts.

The next one you run on the cluster its self. You only need to run one, depending on what suits you best.

 

 

How do you get your System Center Virtual Machine Manager really highly available

Sometimes when I’m invited to visit a customer to “optimize their high available virtual machine manager”, I normally see following configuration.

VMMHA01

 

When I ask why they say it is high available, they normally tell me that they can move the machine from one host to another. Normally i ask now “And what happens when you need to patch the SQL DB, VMM or Windows Server or the storage fail?”

Here comes the point where most people realize that high availability means other things than moving services from A to B.

So now let us think what we need to get our VMM Server high available.

On the VMM Site we need following parts:

  • two VMM Management Servers running in a Cluster
  • two Database Servers running in a Cluster
  • two Fileserver running in a Cluster as Library server
  • two Hyper-V Hosts for VM Placement
  • two Storages with Storage Replication

VMMHA02

 

When it comes to a very big Hyper-V and VMM Environment, I would suggest to run you Management Systems in a separated Hyper-V Cluster. That helps you to keep your VM workload running even when you need to take down your fabric cluster in maintenance mode.

VMMHA03

How to plan redundancy for Scale out Fileser

Hey everybody,

after I posted some of my thoughts I normally put behind Hyper-V redundancy, today I want to show you some examples how you could plan redundancy for Scale out Fileserver.

When to choose a redundancy where only one or two cluster nodes can fail?

That is the most common and easiest why for node redundancy in a cluster. It means you have enough nodes in your cluster to cover one or two node failures. You would choose that cluster config when all of your nodes are in one datacenter or server room and you need no geo-redundant storage solution. Please notice, for a JBOD based Scale out Filserver you need at least a minimum of three JBODs. For converged Scale out Fileserver with Windows Server 2016 you will need 4 equal Scale out Fileserver Systems.

Sofs01

Traditional Scale out Fileserver with Storage Spaces and JBODs

sofs02

Traditional Scale out Fileserver with SAN Storage Backend

sofs03

Scale out Fileserver with Storage Spaces Direct in Windows Server 2016

When to choose a redundancy where you can choose half of the nodes?

In this scenario you can lose one half of your nodes but you need to fulfill some more requirements like storage replications or direct WAN links. You would normally use if you want to keep your services alive if one datacenter or serverroom fails.

sofs04

With Storage Spaces Direct in Windows Server 2016 and RDMA RoCE

sofs05

Scale out Fileserver with classic SAN storage replication

How to plan redundancy for Hyper-V Cluster

Hi everybody,

today again a post out of my daily business. When I’m out in the field and I plan a new cluster, I also need to decide how many and what type cluster redundancy I need to implement. For that I have some thing like a blueprint or decision matrix in my mind which I leverage.

Today I want to give you a small view into this matrix. 🙂

When to choose a redundancy where only one or two cluster nodes can fail?

That is the most common and easiest why for node redundancy in a cluster. It means you have enough nodes in your cluster to cover one or two node failures. You would choose that cluster config when all of your nodes are in one datacenter or server room and you have no additional space or need to replicate your virtual machines.

fail02

Cluster operating with one storage

fail01

Cluster operating with two storages

fail03

Hyper-V Hyperconverged with Windows Server 2016

When to choose a redundancy where you can choose half of the nodes?

In this scenario you can lose one half of your nodes but you need to fulfill some more requirements like storage replications or direct WAN links. You would normally use if you want to keep your services alive if one datacenter, server room or blade center fail.

fail04

Datacenter redundancy with storage

fail05

Redundancy with compute and storage blades

fail06

Different locations with Hyperconverged Hyper-V in Windows Server 2016

When to choose replication?

I normally prefer Hyper-V replication only as a warm standby option. That could be an option for example when you want to secure your datacenter and have no storage replication so that you can reboot your virtual machines on other hardware.

Replications is no replacement for a cluster and I would not recommend to replicate databases, exchange server, domain controller or other applications where the vendor officially supports replication.

How to pass DHCP / PXE through to a virtual machine

Hi everybody,

that’s a post I try to write since a few month. It’s related to an issue or misunderstanding which a customer of mine had.

He wanted to try to get a PXE Boot triggered by DHCP throw a virtual Machine Hosted on Hyper-V. For those of us who are familiar with vitualization, that sounds very simple because the solutions was, he didn’t tagged all VLANs on the Switch and virtual Machine.

For those who are not that familiar, I want to give you a short list what you need to do, to get traffic through you physical and virtual switches right to you virtual machines.

 

Physical Switch Configuration

First thing you need to do, is to tag all VLANs were your virtual Machines will have access to, to the physical ports of you Hyper-V Host and virtual Switch is connected too.

As example: You have one virtual machine in VLAN 10 and one in VLAN 233. Both need connect to your physical network. You Hyper-V virtual Switch is connected to Switch 1 on Port 12 and Switch 2 on Port 14. That means you need to tag VLAN 10 and VLAN 233 on Switch 1 Port 12 and Switch 2 Port 14.

Virtual Switch Configuration

Now you need to configure the virtual switch and that’s the point most people don’t see while working with virtualization. In nearly all Hypervisors you have an operation softwarebased layer 2 switch running. That switch needs to be configured too. That is mostly done via virtual machine settings.

In our example we need to set the VLAN Tag on the switch for a virtual machine on Hyper-V. To do so, you need to change the settings for the virtual machine network interface.

lan

 

You can also configure the switch for VLAN trunking. My Bro Charbel wrote a great blog about how to configure the virtual switch in that way. What is VLAN Trunk Mode in Hyper-V?

In our example you need to know one more thing. In Generation 1 Hyper-V VMs only the legacy network adapter is able to perform a PXE boot.