Longtime readers know I’ve loved Provisioning Server ever since I learned about Ardence way back in 2006.
And I was excited when Citrix bought them later that year, as Citrix added code quality, support, and legitimacy to the whole thing. The only real downside to Citrix owning the product is that they’ve rolled it into their various XenDesktop, XenApp, and XenServer Suites—you can’t buy it as a standalone product anymore:
UPDATE: To respond to some of the comments, Citrix Provisioning Server for Desktops used to be available as a standalone product, but when XenDesktop 4 comes out, it will no longer available standalone. You only get it bundled with XenDesktop Enterprise and Platinum. Citrix Provisioning Server for Datacenters is still available as a standalone product (in addition to the bundles for XenApp, XenServer, etc.)
In the past some people have mentioned that you could buy Provisioning Server through Dell, since Dell OEMed the product from Ardence back before Citrix bought them, and Citrix was bound by the terms of that agreement to continue to provide it to them for some period moving forward.
Even though the Dell edition of Provisioning Server is meant for Dell customers, I know for a fact that some customers have bought it in sort of the “old fashioned” way for non-Dell endpoints. Of course doing this is probably not technically how the Dell OEM thing is supposed to work, and I’m not exactly sure whether using it for non-Dell devices is even supported.
At BriForum there was talk that the Dell OEM agreement would be ending soon anyway, so even if this is an option today, it might not be for long. (UPDATE:I've confirmed that Dell will no longer resell the standalone version of Provisioning Server for Desktops once XenDesktop 4 comes out.) Just to clarify, Dell builds some advanced capabilities for Provisioning Server directly into the BIOS of some of their business desktops, as demoed in Brian Madden TV #7. That BIOS capability will continue and will work with the Citrix versions of Provisioning Server.)
Ardence wasn’t the only company doing this type of thing
So what if you don’t want to buy from Dell, and you don’t want to buy the entire XenDesktop or XenServer suite? What if you just want to be able to use Provisioning Server to manage disk images for some desktops or servers?
Fortunately Ardence wasn’t the only company building a Provisioning Server type of product. A company called Emboot had a product called WinBoot/i which was functionality very similar to Ardence / Citrix Provisioning Server. It turns out that emBoot was bought by Double-Take about a year ago, and the Winboot/i product was released as Double-Take NetBoot/i.
In the past few months, NetBoot/i has evolved into what’s known today as Double-Take Flex. Perhaps the greatest thing about Flex is how it’s bundled. You give Double-Take some money. They give you the product. The end.
How Double-Take Flex works
As I wrote, the architecture of Flex seems very similar to Citrix Provisioning Server. Perhaps the biggest difference is that Flex mounts disk images via iSCSI, where Provisioning Server uses their proprietary UDP-based protocol. Citrix claims theirs is better because SCSI was never meant to run over a network, so iSCSI is just sort of a work-around. Double-Take claims iSCSI is better because it’s much more universal.
To that end, Double-Take Flex does include it’s own built-in iSCSI storage server, but the beauty of it being iSCSI is that it’s optional. What I mean is if you want to use it, fine. But if you want to use an iSCSI SAN or some other iSCSI block host, go for it!
This is kind of nice because Citrix has been dinged in the past for the reliability and high availability capabilities of the Ardence storage host. So with Double-Take, if you don’t want to use their host or if you want some other storage host that’s super-reliable, go for it.
And that leads us to another major difference between Provisioning Server and Flex. Like Provisioning Server, the client is “configured” simply by changing the boot order preference in the BIOS of your endpoint so that a PXE boot is the highest priority. The client boots up and a bootstrap is downloaded via TFTP. (Both the PXE and TFTP servers are built-in to Doulbe-Take’s management server, which you can choose to use or not.)
The client bootstrap then contacts the Flex management server where it connects the client directly to the iSCSI provider. (This bootstrap can also provide an AD user authentication box which allows user- and group-based disk image assignment.) Once the client is connected to the iSCSI host, the Flex management server is completely out of the picture.
Also like Provisioning Server, Flex handles all the stuff you’d expect it to handle: Over-loading of drivers in disk images so they work across disparate client devices, dynamic injecting of machine identifiers from AD, etc.
Double-Take Flex is $95 per concurrent connection for desktop OSes and $395 if the client is running a server OS. The current version supports 32-bit and x64 OSes, and Windows 7 and Server 2008 R2 are fully supported.
Flex is not without it’s limitations. They still don’t have an offline capability, although they claim that’s coming.
So now what?
Double-Take is in kind of a hard position with regards to the desktop virtualization space. The company is obviously known for their data replication and data protection technologies. It’s easy to understand why they bought Emboot, as the ability to create a backup bootable disk image across a WAN is a pretty killer feature for Double-Take’s other products. I feel like in some ways, they’ve almost “accidentally” found their way into the desktop virtualization space, and now they’re sort of a solution looking for a market.
Certainly there’s value in being a “Citrix Provisioning Server without Citrix.” But beyond that, what can they do? Do they partner with a client hypervisor and combine Flex with the other Double-Take products to move and mange disk images around? (Or is this a commodity since the client hypervisors already have similar capabilities built-in?) Do they partner with user personalization vendors to move user data around? Do they compete with Wanova?
We’ll see how this unfolds. I definitely like that Double-Take has a “real” brand, so it’s not like they’re some unknown startup fighting from scratch in our market.
What do you think? Have you used Emboot or Double-Take Flex? Where do you see them fitting in this space?