Security Analyst – Jeff Soehner CISSP, GXPN,GPYC,GMOB,GCIH

One of the things that can set apart a business is failover technology – lets’ face it stuff happens. Hard drives develop errors, power fails and your computers just stop. As a MSP I can wait to find out about it a few minutes after it does from my clients (who are not very happy because it failed) or I can find out with extensive monitoring that is constantly checking the hardware/software environment but I can’t really do anything about it unless we configure additional hardware/software to kick in when it happens. Until now those setups were large and expensive and involved clustering file systems, multiple servers and quite frankly would require dozens of man-hours to setup and maintain. Disaster recovery involved thousands of dollars per month to have on hand just in case you needed it.

Along comes Windows 2012 Hyper-V with features that help bring the cost of having the benefits of this technology to a small business for a few thousand dollars per year!

Enter Cluster aware updating – this new feature of Hyper-V allows any small to medium enterprise (SME) to implement two Hyper-V servers with enough memory to run all of the virtual servers they need to operate their business (Exchange, SharePoint, File server, SQL, etc.) Most systems come with redundant hardware (power supplies, hard drives, etc.) so a single point of failure is all but eliminated but what about updates and maintenance? If you want to keep everything running or even just want to test your recover options in the event of failure you need to fail over your live system with as little or no downtime right?

Let’s looks at an example below

Cluster Aware Updating initiates an update. It is determined that one of our Hyper-V machines needs an update so it is downloaded. CAU migrates the VMs off to another member of the cluster.

Next is a screen of the CAU progress as it begins to apply the update

After the update is applied CAU issues a restart of that member of the cluster.

Once the restart is complete for the patched Hyper-V machine all members are scanned again for patches

Migration back to preferred machines occurs once all Hyper-V machines have been updated and restarted.

All of this can happen automatically just as you schedule Autoupdates for all of your desktops. There is no need for an administrator to manage each patch and to manually apply them. You can still have little or no downtime and have complete fault tolerance for your SQL and Exchange databases which means no interruption for your business.

Now did I mention that it’s all free! Not one maintenance fee, not one software license or add-on cost associated with this solution – all you need are a few machines to run Hyper-V and your finished. Now I would like to see VMware come up with something that tops that!

I recently had a problem when I upgraded to Hyper-V 2012 with an older test machine (DC5750) that just wouldn’t work with the new kernel. I decided that it was time to create a new Cluster and dreaded the Import/Export that I was going to have to do. I thought this would be a great time to test the Replica feature. Not only will it allow you to replicate VMs onto another Hyper-V machine for disaster recovery but it will also allow you to replicate to another cluster!

Here I show you a snap of the Failover Cluster Manager with both of my clusters (MyCluster is the old cluster I am migrating from – you can see Hyperv8 is the only node and Cluster1 is the new one). You have to create a Replica Broker for Replications to occur on a cluster and I have now setup SW1 to replicate to the new cluster. Now I have all four of my VMs configured to replicate changes ever 5 minutes and can take my old cluster offline when I am ready. It will require me to start the new VMs on the new cluster but I can do this at any time.

Hyper-V Replica keeps a log of any changes to these VHD files and replicates those changes to the other VM. This results in a fairly quick time to recovery if any issues should ever happen to your main cluster. Initial replication can even be done offline to a disk and imported into the other site so bandwidth issues and large VMs are not a problem. You can even do all of this with a single NIC!

I am not happy that at the time of this writing they still do not have any management upgrades for Windows 7 (you will need to have a full version of Windows 2012 or Windows 8 to manage these new features) but I like the fact that the old Hyper-V management application will still allow you to work with your VMs.

Windows has hit this one out of the park and has challenged both Citrix and VMware to step up to the plate for most SMBs. I hope you find it as robust as I do and consider implementing your own CFS.

It’s been a while since I wrote about any VM backup software (or for that matter ANYTHING) but I wanted to take some time to update my readers on a great little software from the folks at Trilead. I have been using this software since the early version 3 releases and they lost my attention when they began to require the VMware guests be shutdown before they were backed up. Now in version 4.0.37 I noticed that they have added that functionality back along with Hyper-V support! (actually Hyper-v had been added earlier than 4.0.37 but now that I have a Windows 2012 test machine I noticed that it was supported).

They have added a two server restriction so you will only be able to connect to a maximum of two servers but as long as you don’t have more than two nodes in your cluster you can use the Free version.

You can backup all of your virtual machines running on your Hyper-V cluster and you can even move them by backing it up and then restoring it to another host (unfortunately you cannot use the replication feature in the free version although who would want to – migrating from one hyper-v to another in a cluster is easy).

You can only perform a full backup on any of these vms but since this is a free product and you can do it while the guest is running I think this software is a great plus you can check them out at http://www.trilead.com/Editions.   Where else can you find a software that will allow you to backup a vm – convert it and then import it to a hyper-v cluster that is free?

I wanted to touch base with some of you and share my experiences with virtualization. For those of you who have followed some of my posts you may be asking ‘how can I export/import’ between the different virtual hosts. (I have been asking myself this question for a few years now). As some of you are no doubt aware there are a number of tools available for a price that will enable the user to make this migration with as little time as a can of coke and some tim-bits but for the average tech out there these tools are expensive. Some of them work great between one platform or another but not all of them work perfectly. As I am a man on a budget and choose only to spend money when I have to I tend to lean towards tools that are free that, although they may take time and expertise to operate, make my bottom line, and that of my clients, easier to swallow.

Part of the problem with changing hypervisors is that apps like Xen and Hyper-V use vhd files while vendors like VMware have made their own type called vmk. There are some tools that will convert from one file type to another but they don’t take into consideration the different architectures that you made the VM image with and plan to run it on. Then there are drivers – those can blue screen a windows system or hang a Linux based system if you aren’t careful.

Well I recently tried to migrate some vms from my ESXi 5 machines onto a Hyper-V cluster and made some interesting observations.

OpenSUSE has a hard time converting from vmk to vhd because of the sixe of the resulting vhd reporting a superblock size difference. If you run resize2fs on the disk you can actually get the vm to boot on the Hyper-v system. (Might require the Integration tools – more on that later)

AsteriskNOW runs on CentOS and has no problem running on Hyper-V clusters but I warn you – you must set the MAC address to be static on a Virtual Network Adapter in order to have the IP come up on the other Hyper-V hosts in the cluster. (Incidently I have used VMs to run asterisk in my home office for almost a year now without any issues).

We need to do a few things to add the Hyper-V Integration tools for Linux to make this complete. You need to install the GCC compiler and any dependancies to be able to compile the Hyper-V tools (storage, VM bus, synthetic NICs, etc.) Once installed you should see the boot screen resemble something like this 

Now that we have confirmed that the guest is back online let’s shut it down with the tools.

Next we can add the VM to the list of HA apps on the cluster.  Once we have done that let’s start it up again to confirm it can boot.

Now if one of my vm hosts goes offline (loss of power, network, etc.) then my PBX is dynamically moved to a new host and brought online again with a short downtime (about 15 seconds) shown below.

It sure is nice to have AsteriskNOW running on a free cluster now (without the cost of running enterprise software .