Citrix had been cloud computing ever since. In fact, Citrix started doing professional Cloud Computing in 1995. They improved their private cloud approach in 2002 by launching Secure Gateway (and all it’s successors). They already did cloud computing when no one even knew about cloud computing. Maybe Citrix is the cloudiest company on the globe.
Citrix dramatically improved their product over time. A big step forward was FMA. Maybe some of you don’t really like FMA, but I think it’s great. But there is one drawback about FMA: it’s expensive.
With IMA you could create a single remote desktop server and add Citrix XenApp to it. That’s it. No data base needed, a single MDB file will do. Install your web interface on the same box, finished! Add a second remote desktop server, including web interface, and you have, what I’d consider to be a farm; with full redundancy. OK, management is not possible as long as the server, containing the data store, is down.
FMA is different: There is a strict separation between back-end and front-end components. Even though I do know it’s possible to install all components on one box, I would strongly advice to keep them separated.
There are three mandatory components: Data base, controllers (also called desktop delivery controllers, names change frequently) and StoreFront. (Plus license servers, …)
The data base had to be redundant as it was essential to the farm. You could not launch a single application as long as the data base was down. This was mitigated when Citrix introduced connection leasing, but a stable data base still is mandatory.
Controllers are essential too: same here, you can’t launch an application as soon as all controllers are down. Same is about StoreFront.
So a fully redundant XenDesktop / XenApp 7.x deployment consists of three (!) data base servers (one of them, the witness server, may be SQL Express), two controllers and two StoreFront servers. A “somewhat stable” deployment for a small company consists of, at least, a data base server, and two boxes containing controller and StoreFront functionality, so three servers.
These may be Remote Desktop Servers or virtual PCs. I call these: workers. They may run on bare metal as same as on any hypervisor you like (as long as it’s VMWare, HyperV, Xen, Amazon Web Services, Microsoft Azure and many more). I won’t go into in this. They pay themselves as they do real work.
So let’s go back to the back-end components.
They are some kind of a set it and forget it infrastructure. If you look a bit deeper into these, there is some important work for an admin: data base backup (including regular restore tests!), frequent updates (as Citrix releases a new version every 3 to 6 month) and some more.
Did you ever think: why do I need to keep all these costly components? Bet your life: I thought of getting rid of them several times. But moving all of my (my costumer’s) environment into the cloud is no option in many cases, so I have to keep them on premise.
Let’s think a bit about it: Why? That’s easy: data is mandated to be on premise, so back-end components need to be on prem as well. Right?
Citrix now offers Citrix Cloud services. Maybe you think: just another f***ing cloud provider? No. That’s definitely wrong. Citrix does not run any cloud services at all, instead they host on Microsoft Azure. And Citrix does not want host your workers, they never will. Instead they offer all necessary back-end components. Fully redundant, perfectly sized, updated continuously, including Citrix licenses.
I have been on a sales workshop by Fabian Kinle yesterday. Fabian is a hero of German, of European Citrix sales. Yesterday he wanted to sell Citrix Cloud Services. And he asked: Would you sell Citrix Cloud Services to your costumers. “I would not do” I replied. Fabian didn’t like this on first sight. “But I would guide my costumers all the way through a XenApp / XenDesktop project. In the end, we would decide where to host all these back-end components. Citrix cloud services is, indeed, a very sexy option: I can get rid of all these back-end components and focus to the front-end. From perspective of a consultant this is sexy, as back-end components just cause trouble, but don’t bring much revenue. From perspective of the costumer, it’s pretty much the same.” Fabian started smiling again.
Yes, I would think of that. I would think of that for a rather small environment (since licensing now starts from 25 users), as I get full redundancy for rather little cost. I would consider using it for huge costumers as well, as Citrix will be responsible for all the life cycle management, like scaling it up to a proper size and updates. Your back-end components will always be shiny and fine. Being the architect, I would also like it, as sizing back-end components is my peace of cake no more.
And being the CFO? Hey, I don’t have to buy hardware and licenses and then pay for a year by year subscription, instead, I will rent. It adds flexibility as I can add or remove licenses whenever needed. Don’t forget: after reducing stuff you will still have to pay subscriptions for now no more needed licenses as further growth may bring users back.
Citrix also tries to keep your workers as independent as any possible from cloud providers. They will release tools to help you moving your workers. From premise to cloud, even better, they’ll help you moving from AWS to Azurre (that’s obvious), the other way round (that may be a bit of surprise), or even from cloud to premise (even though no one nowadays may think of this). They don’t care where you host, they’ll help you as long as you use their product.
There is something they care about: Keeping you environment up to date. Maybe even more: They keep their own environment (so your hosted StoreFront, controllers) one step ahead of retail versions. This does not mean you have to update your VDAs on a daily base: there is a broad range of backward compatibility. Just update your part of the site (farm), when ever you feel like updating. Update it, when ever you see a benefit.
The rest is simple maths. Are costs nice, just fair or even insane? That’s your job to do.