Running Multiple Hypervisors Under vCenter: A Quick Look At Hotlink

Over the last couple weeks a very common question I am getting from customers is around switching off of VMware and onto another hypervisor. Usually when we go through the exercise to determine if this is something within their comfort zone we find quickly that the idea of rip and replace is much more of a burden than keeping the current infrastructure. But with that said, things are a changing and people are looking at a plan B so they are not married to a specific vendor incase of some sort of dramatic change, lets say pricing or feature set for example.

Until recently I could honestly say there wasn’t any alternatives that we would recommend that was apples to apples in features and scalability etc. Plus, even if a customer moved to a lateral competitor (Citrix or Hyper-v) they same “locked in” situation would occur. Now, only if there was a product that could manage all the different types of hyper-visors with the best of bread management software on a single platform?

Well we are all in luck because there is a new company that promises to help with this situation. Hotlink was founded last year and will be launching their new product, Hotlink SuperVISOR, very soon and I can say looking over their spec sheets that I am excited to see if this will be as advertised!

What Is it exactly:

In its simplest form it is a layer that sits in-between the hypervisor layer and your management console (vCenter for example).  Using their unique tools set including virtual object bus, transformation technology, proxy and integration services it allows for heterogeneous environment. This means, good or bad, you can run a multitude of different hypervisors under one single platform.


One thing that I do like about this technology is that it does take advantage of your best of breed products. For example, its first management plugin is designed for VMware vCenter and looking over the feature set this is a wise decision. Customer familiar with working in this management console will find the transition smooth with little to no disruption allowing them to leverage existing skills.

As well, you can now mix and match your hypervisors to match your application needs. This both increases efficiency and decreases cost as you put enterprise class programs on VMWare which is expensive and put tier 3 applications on Hyper-v which is less expensive. This puts you in a position to avoid vendor lock-in and if you are already running multiple hypervisors provide a single management console reducing your opex.


I want to be careful when pointing out good vs. bad when reviewing this product because to be transparent I haven’t seen a demo copy or tested it in the lab as of yet. So instead I just have a lot of questions about the functionality, performance and other technical details.

For starters, I am not sure on the performance overhead of my host machines? I don’t know what this does to my environment if lets say I structurally built around VMware now running several different products under the same hood? I don’t know how this would affect my storage infrastructure and included API’s from EMC, NetApp, etc? Design, deployment, troubleshooting are all questions at this point. This is just the tip of the iceberg. I will say I would be a bit nervous putting this layer in my environment without a firm understanding of all impacts it would put on my infrastructure.

What it won’t solve:

It still won’t address any licensing issues around cost reduction. True you could say move your file servers to Hyper-v which is free with Windows server licenses and only keep your primary machines under VMware but that falls into the 80/20 principle and willing to bet that most of your production applications are high to mission critical and cannot afford any downtime, which is why people move to VMware and pay the extra premium.  However it could help lead down the path were you could give VMware a solid threat to migrate and have a powerful tool at your disposal.


The base price for the SuperVISOR platform is $25k, which includes support for vSphere + 1 other hypervisor and 5 hosts. That is all the details I have at this point. As I hear more I will update this posting.


Overall this is a great step forward and depending on execution could change the virtualization landscape. I would assume that there will be a group of similar products over the next couple months as this idea gains traction. So I will be curious to see how fast Hotlink can move to market and get adoption going. Looking to seeing more updates.

Mounting a VMFS Datastore Using ESXi Install CD

Recovering an ESXi install that won’t boot can be a frustrating and difficult process. What do you do if the usual options don’t work; repair option on the install cd or booting ESXi from a USB stick? As well, wouldn’t it be nice if you were in a rush and just needed to get information off the VMFS datastore rather than rebuild the whole host? Good news, there is a way to mount a datastore to gain access to the information.

  1. Boot from an install disk, press ALT+F1 to get the console.
  2. Login with using the user root (password will be blank)
  3. Run ls /vmfs/devices/disks/ to validate that ESXi can see the host disk
  4. Load the vmfs3 driver using the vmkload_mod command.
  5. Now run vmkfstools –V to mount your existing datastores
  6. Finally, use SSH or SCP to copy files from the datastore to another location.

Hopefully this will save you time if you have an ESXi go down and all you need is to access the data to a new host.

CapIQ Can Help Streamline Your Virtual Environment

One the primary goals for IT is usually better efficiency, which tends to be a contestant obstacle as new and larger technologies are released. VMware and virtual machines is no exception to this challenge. VMware does make a tool that is pretty helpful when it comes to managing and planning your capacity needs. Capacity IQ uses the following tools to help predict what physical resources will be necessary to run a virtual machine within your performance SLA’s:

  • Physical Capacity-CPU, memory, disk space, I/O, etc…
  • Virtual Machine Capacity- Measurement of abstract capacity. Basically converting physical properties into virtual machine measurements.
  • Past through Present Trends- Tracks speed of capacity and gives insight of where and how fast it is increasing, decreasing or staying stagnate.
  • Estimated Time Remaining- This helps with planning for future upgrades and refreshes.

Once you have gone through the program and looked at the different dashboards you should be able to go through an extensive amount of information. You can now turn that data and optimize your host for capacity regaining unused resources. To do this select the Views tab, select Virtual Machine Optimization – Summary.

And you should see something below:

Which will give you the following:

  • Assess Virtual Machine Capacity usage.
  • Identify Oversized Virtual Machines.
  • Identify Undersized Virtual Machines.
  • Discover Idle Virtual Machines.
  • Discover Powered-off Virtual Machines.

You can also use a helpful tool that will allow the creation of scenarios. These “what-if” scenarios would show how capacity could change based on certain conditional changes without making actual changes to your virtual infrastructure. This is really helpful for when you want to know what deploying an application would do to your environment in advance versus just throwing it in your environment and hoping for the best.


MSRP is $495.00 per processor and you licenese it based off of vCenter servers.


Mananging capacity can be one of the most difficult parts of managing and infrastructure. Getting the most of what you have and knowing when to upgrade or expand can feel a lot like playing the stock market. CapIQ can help resolve most of these issues.

More Information.

VMware vCenter Update Manager 4.1 Sizing Tool

VMware has a calculator that will estimate the size of the VMware vCenter Update Manager 4.1 (VUM) databases and patch store. Once you enter some key information it will spit out the following results:

  • Update Manager 4.1 database deployment model recommendations
  • vCenter Update Manager 4.1 Server deployment model recommendations
  • Initial disk space utilization in MB for database, patch store, and temporary space
  • Monthly disk space utilization growth in MB for database and patch store
  • The higher and lower bounds on the estimation, assuming a 20% variance

You can find the estimator here.

Please note some other best practices around VUM:

  • You should use a separate database from your vCenter Server database
  • Install VUM on the same host as your vCenter Server Host

vShield Suite Introduction

Securing your virtual environment can at times be a very complex process.This is especially true with cloud environments or multiple tenant environments. Also, there is a good chance that there will be some security concerns about high consolidation rates. There are several good 3rd party options from the primary security vendors (Symantec,McAfee, Sophos, etc…) as well as some up and coming startups (Catbird). As well, VMware offers a suite of products, vShield Family, to help manage your virtual environment. This suite includes the following:

  • vShield App: Applications protections against network-based threats. Basically this monitors all traffic between your vm’s will applying a policy that limits what can be transferred based on policy’s. Think established DMZ not talking to Medical records.
  • vShield Edge: Perimeter based network security. Firewall, Network Address Translation (NAT), Dynamic Host Configuration Protocol (DHCP), Site-to-Site VPN, Web Load Balancing, Port Group Isolation, Policy Management, Logging, and Auditing.  Could replace hardware applainces such as f5.
  • vShield Endpoint: Offloading of AV processing. Can only be used with vSphere 4.1.
  • vShield Zones: Hypervisor-Level Firewall protection between virtual machines.
  • vShield Manager: Management Interface for all of the vShield suite and 3rd party security services.


vShield App and vShield Edge are both $4,688.00 MSRP for a 25 Virtual machine pack with 1 year of support. While vSphere Endpoint is $1563.00 for a 25 virtual machine back.

For more information click here.

vMotion Improvements!

Here is the situation; you have built out your virtual environment the best way possible. I am talking about the best servers, storage, and network money can buy. From a bench mark perspective it is the best and everything runs perfect. However, you run into a situation where you need to vMotion several servers at a time to shut down a production server for updates.

Then you realize even though you have the best environment you still are limited to a static amount of concurrent tasks. As well, large vm’s with bigger memory configurations would be sluggish or wouldn’t even migrate all. Finally, even though you invested in a huge 10GbE network with your fancy Converged Network it seems there is always a bottleneck. What to do?

Upgrade! The good news is that with vSphere 4.1 the amount of concurrent vMotion task has been significantly increased see chart below. They call it Scalable vMotion. It does several new things:

  • Restructured how vMotion takes advantage of the network.
  • Better optimization of memory handling.
  • Optimized vMotion convergence logic.

The engine allows a throughput of 8GB/sec on a 10GbE link, which is 3 times the performance of version 4.0. This will significantly improve data-center performance and help with larger migrations. As well, this should improve the adoption among cloud service providers and the better acceptance for the private cloud.

Using Older Hardware with VMware ESX; Make Sure It Is Compatible!

Part of planning a VMware deployment is deciding the hardware that it will go on. A common solution to reduce costs is to use existing infrastructure of older machines and just place VM’s on this platform. While this will work there needs to be some considerations when deploying on existing hardware.

The very first thing to always do is check the Hardware Compatibility List (HCL). This is the supported list from VMware with “guaranteed” approved hardware.

Also, 64Bit seems to be a reoccurring topic. There are strict limitations what will and won’t work and VMware has built in safeguard to limit installation on unsupported chip sets.

Another huge consideration is to evaluate your virtual machine roadmap. For example, your older hardware may be able to support ESX 3.5. If you were deploy based on that, then wanted to migrate to 4.0 or 4.1 you would be stuck buying new hardware and dealing with a migration. Which isn’t bad except for the fact you need to make sure your CPU will be compatible with VMotion.

Also take into account there is a limit to the amount of compatible machines. Below is a quick summary of the compatible HP systems for ESXi 4.1. As you can see the list isn’t too long. Granted this is just one vendor, it does show that there needs to be careful thought when planning out your hardware.

Granted, I do recommend using older hardware when possible. A good example is test/dev environments or a lab type situation. That being said any thing to do with production machines I would think twice before re purposing older machines.

How To: Changing The Name of a Virtual Machine While It Is Running

Did you know?

That if you change the name of a virtual machine while is powered on; the files that consist for that VM will not be changed.  This would mean that vCenter would display a different name that would be found in the file system level. To resolve this while the VM is running it is recommended that you:

  1. Change the name.
  2. Use VMotion to move the machine to a new datastore (This will rename the files that are copied).
  3. VMotion back.
  4. Done!

This will avoid confusion and having to shut down the VM for any scheduled downtime. On the flipside, you can do it the proper way:

  1. Make sure there is no snapshots etc.
  2. Shutdown the virtual machine.
  3. If you are using VirtualCenter, remove the virtual machine from the inventory but do not delete the files from disk.
  4. Connect to the ESX Server host on which the virtual machine resides over SSH.
  5. Unregister the virtual machine using command: vmware-cmd -s unregister <path to config file>
  6. Where <path to config file> is the path to the configuration file as determined by ‘vmware-cmd –l’ . ‘/vmfs/volumes/storage1/vm1/vm1.vmx’
  7. Rename the folder, .vmx file, and .vmdk (+ flat) file to match the new name.
  8. Edit the vmx file to reflect the name of the new descriptor file.
  9. Locate the scsi0:0.fileName line.
  10. Save the file and exit
  11. Edit the .vmdk file to reflect the name of the new flat file.
  12. Locate the Extent description section of the .vmdk file.
  13. Register the virtual machine.
  14. Add the virtual machine back into VirtualCenter inventory using the Virtual Infrastructure Client by browsing the data store, finding the .vmx file, right-clicking and adding it to inventory.

For more details.

VMware Pricing Model Change

There is some big news making its way around the blog community and it has some potential to impact you if you were planning to implement Site Recovery Manager (SRM) in to your VMware environment. Currently when you buy SRM it is sold as a per-cpu model. This allows for easy license counts and technically an all-you-can-eat environment (outside of hardware limitations).

The new model that will be released on September 1st 2010 will be switching to a pay-per-vm model. This will change the way to plan and purchase SRM drastically. For one, the minimum package size will be a 25 VM pack. So for example is decide to protect 2 machines but need 26 licenses, you will have to buy 2 25 packs, which could be expensive and a bit overkill. As well, some customers only need 2 licenses at a time and may have a difficult time getting budget to pay for such a large purchase. In theory, according to VMware “this new pricing model will make it easier and less expensive to take advantage of the vCenter product capabilities.”

This model will be based on a rolling average. So if you hit 250machines in December but the rest of the year you hover around 100, you would take your daily maximum total of virtual machines (average around 153) and that is what you would buy.

There are a few things to note and take in consideration, for instance, what if I already some licenses? VMware will be providing a transition plan to allow for you to exchange your per-processor licenses that are based on the new model. I don’t know what the exchange rate is, and VMware hasn’t given a lot of details on this.

What if you want to keep your current per-vm model? Again, according to VMware you will continue to use and purchase SRM licenses as normal until December 15th 2010. And even be able renew support as normal. This is still vague and we will continue to wait for further information from VMware. I am assuming there will be a time when VMware makes the customer convert over to their new model but I don’t know the exact date.

I also don’t know the conversion rate. It could be 1 for 1, it could be 1 for many. It isn’t clear. I am sure there will be a lot of questions and concerns from people as the move or decide to adopt SRM.

One huge question a customer brought up is about mixed environments. This would take place is you didn’t buy any more licenses and needed to have more SRM. You would still have per-cpu and now per-vm? Not sure how that will work.

One Final note this doesn’t just affect SRM, it also impacts: vCenter AppSpeed, vCenter CapacityIQ (early 2011), and vVenter Chargeback. If you were planning to buy these products I would make sure you did it soon and strategically.

More information to come.

VMware Page

Jumbo Frames for ESX/ESXi

One thing it seems is overlooked when architecting or troubleshooting a VMware solution with your SAN environment is the use of Jumbo Frames. Most Ethernet switches have Jumbo Frame support and can handle the higher Maximum Transmit Unit (MTU) This is used for a variety of reasons, and especially comes in handy if you want to use VLAN trunking or need the larger transmit size.

When there are performance issues over the network and your storage a consideration is the actual size of the Ethernet frames. The maximum is typically 9216, so it is recommended to size the payload to the maximum allowable setting. This helps makes sure to account for any extra bytes, such as, header (18 bytes), VLAN tag (4 bytes – Tag Protocol, User Priority, Cannonical Format Indicator, and VLAN ID), and addresses. If you don’t take this into account your environment will have issues communication and you could suffer severe performance issues.

How To:

Once you set-up your MTU on your Ethernet Switches you will need to adjust both your vSwitch and then the VMkernal port that assigned to the vSwitch.
To enable Jumbo Frames on your vSwitch:

1. Using  vCLI  connect to your ESX/ESXi host

2. Execute the following Command:

vicfg-vswitch -m <MTU> <vSwitch>

You will want to set the max MTU possible that your virtual network adapters connected can handle

3. Verify:

v icfg-vswitch –l

To Enable Jumbo Frames on a VMkernal port

1. Using vCLI connect to your ESX/ESCi host.

2. Execute the following command:

esxcfg-vmknic –a –I <ip address> -n <netmask> -m <MTU> <port
group name>

 This will create a port on the VMkernal allowing for Jumbo Frames.

3. Verify:

esxcfg-vmknic –l


Hopefully this is useful and could solve the mystery performance issues. Make sure you adjust the MTU on your storage array, EMC, NETAPP, Equallogic, etc.