Would You Move to Windows Thin Clients?

mcck asks: "My workplace is getting ready to study this problem in depth. From my preliminary research, there is very little savings when moving to a thin client environment that isn't based on Linux. Current thinking is that we will have to stick with Windows, so Linux is out for now. Citrix maxes out at around 10-25 users per server. I haven't studied Windows Terminal Server as deeply, but it looks to be about the same. Once we buy the 100 servers we would need to support 1000 or so of our users that would be migrated, plus increase our system administration staff to adequately support those servers, it looks doubtful that we would save much money at all, if any. Plus, if we upgrade all of the related desktop hardware to snazzy new official thin client boxes instead of trying to get more life out of old hardware (which is what they want to do right now), costs go up even more. So here's a question for anyone who has studied this issue, or seen its consequences at their workplace: Is thin client really a cost-saving approach to a large user environment?"

"Most users will be running basic MS Office apps, Groupwise for e-mail, and accessing some Oracle databases. A consultant hired for preliminary recommendations is saying that we should run Windows XP on the thin client boxes, not even the embedded version but the full one. Additionally, some of our users have more powerful applications like AutoCAD and ArcMap. We have already determined that those users will not be moving to the thin client machines.

Our department has spoken with a Citrix support/sales person who claims you can support up to 1000 clients on a single Citrix server. That seems so far from what I have generally read that I have a hard time buying it. Can anyone corroborate that claim? Again, most users will be using Office, Groupwise, and accessing Oracle DBs.

Does anyone have any experience with a workplace making this sort of migration? I would love to find a way to make it work, but from the research I have done so far, it doesn't look like we are going to get any cost-savings (unless they miraculously decide to go with Linux)."

Comments

Some observations and rules of thumb.

[sybarite]

I deploy and support this type of environment for a living (until I can earn my living with Open Source). While the number of users per server depends largely on what applications that you are running, a good (conservative) average number is about 50 users per dual-processor server. I tend to deploy dual-processor machines as their are diminishing returns on quad-processor servers (For example going from dual- to quad- processor increases your user count per server from 50 to only about 75 or so). These rules of thumb are on your average Pentium III server with about 1.5 to 2 GB of RAM. The Office software and Groupwise will conform well to this rule of thumb. Not sure on the Oracle apps, but if they are well-behaved 32 bit applications (read no DOS, 16Bit) they will run fine. Obviously you will want to pilot this environment to bench mark your specific results. Servers with Pentium IV Xeons will probably scale much better.

You will definitely want Citrix here for the advanced management and capabilities over Terminal Services alone (application publishing, advanced load balancing, managment console, etc).

If you take the benchmark numbers I mentioned earlier and add 20% or so for redundancy, you are looking at a farm of about 24 servers vice 100. Using the management capabilities of Citrix and server cloning techniques, administration of this farm will be be pretty easy. A single, experienced Citrix administrator can handle most of the level 2 and 3 support for this farm. With server cloning, adding additional identical servers for growth/redundancy down the road is easy.

You have correctly identified users of AutoCad and ArcMap as poor candidates for this type of environment due to the heavy requirements and graphics of these applications.

I disagree with the consultant that full blown XP is the best solution for the client. He/she may be hedging their bet for any Windows based applications that would not run well under Terminal Services/Citrix. If this is not the case, there are several Linux-based thin clients that would work well and would have a lower cost.

Would you move to Windows Thin Clients? (Yes!)

[rocket rancher]

I have four servers configured with a single PIII 1.4GHz CPU and 2GB of SDRAM in a Citrix farm supporting 1100 Mac and Unix users for MS Office apps, Lotus Notes and MS Internet Explorer. *My* Citrix sales engineer claimed that only 15 to 25 concurrent users can be supported per CPU, but I have found that 4x that is easily doable.

Individual users have different ways of working --not everybody is going to slam the farm in the same way at the same time every time they need to use a published app. Even with all one hundred of my client access licenses checked out, CPU utilization and paging on individual boxes in the farm stayed well below my alarm thresholds.

Generic productivity apps for word processing, spreadsheets, presentations and email just don't demand much from a CPU. Given the apps you intend to support (Groupwise, MS Office, and some Oracle front ends) I can't see you needing even 10 Citrix servers. Your best bet is put up a test farm and then perfmon your CPU utilization and swapping. Baseline it and then start adding users. Citrix have a very liberal demo program and you should take advantage of it.

As far as corroborating the claim of 1000 clients on a single Citrix server, I supported over twice that many (2270 to be exact) UNIX users with a single Citrix server, a PII running at 233MHz with 768MB of RAM. I started with 15 concurrent access licenses and 512MB of RAM. I added 15 more access licenses and another stick of SDRAM after the early users started spreading the word to the rest of the users how useful it was to be able to take care of company documentation right on your HPUX box and not have to wait for one of the five bull-pen NT workstations to open up. I published the MS Office 97 suite, plus Lotus cc:Mail and Visio, and the server never bottlenecked at the CPU or in paging. I also got to surplus those 5 bull-pen boxes and save the company the annual support fee we were paying to our out-sourcer, half of which, btw, showed up in my xmas bonus that year. :)

If you are going to publish apps with low CPU utilization like Word and Excel, I think you can easily support your thousand users with a handful of Citrix boxes.

Hell no! Don't go there!

[Zocalo]

I work in an office that has a mix of Wyse thin clients to front-end Citrix and traditional Windows and Unix workstations at a large utilities company. When we have a problem with an application; we go direct to the source for on-site support; Microsoft, Citrix, whoever, no questions asked, so I can be pretty damn sure that our Citrix install is up to spec. Despite all this, the thin clients suck. Big time. I'm just glad I only have to use one of the damn things and not administer them. Warning: Everything below this may be an Anti-Citrix rant - I positively despise the fucking things, so things may degenerate!

Let me reiterate one point: This is a user's perspective of Citrix from someone with a predominantly UNIX and networking technical background. I do *not* have a clue about the finer points of managing Citrix installations, nor do I wish to after the last few hateful months with it!

The big selling points of thin clients are supposed to be a lower TCO and better security and management. In short, for WinTerms at least, this is pure marketing bullshit. Sure, it's a couple of hundred bucks a seat cheaper for your hardware and your end users can't install a macro virus or whatever. Well, actually, that last point is wrong. It's perfectly possible to have a user trash your Citrix server if the code happens to get executed there because your AV vendor wasn't on the ball or a patch was broken, only now they can effectively take down twenty other users at the same time.

Another thing that they don't tell you is that software licensing is a fricking nightmare - 1,000 users and 500 seats still equates to 1,000 licenses in many cases. We use Microsoft apps a lot, and they are totally inconsistent in their licensing requirements for thin clients, so much so that we now have full time staff just looking into thin client software licensing issues. Some other vendors are better, others are worse. Others are MUCH worse. More $$$ on the TCO.

Let's look at that TCO a little, while we are here. A tier 1 Windows corporate PC (after bulk discount) is roughly 1000 for us, including all of your office apps (cheap because they are bundled). A Wyse term is setting us back around 700, including your hopefully per-seat software licenses (not as cheap because they are unbundled, but on a bulk purchase scheme). *But* for each 10-20 users, you need a server. We run at 15 and still have performance issues, and we are talking dual Xeon boxes with 2GB of ECC RAM here; not cheap. The hardware/software costs are, in fact, about the same per seat, if anything thin clients are more expensive.

So, that leaves the management aspect of TCO. OK, there's less patching to be done, right? Well, actually no, since all the updates on our traditional desktops and laptops are handled either by the AV application directly or via a systems management package. No savings there. Warranties? Nope. That evens out in the same way that the hardware costs do. First line support costs? No, users still have the same problems with Office and what not. Second and third line support costs then? Ah! Finally a difference; you get to cut back on all your school leaver PC techies at near minimum wage and hire some Citrix Consultants instead, sure you only need half as many, but they come at three times the salary.

Citrix itself comes across a horrible hack to anyone who has used UNIX thin clients over X11. Performance sucks if you try and do moving video; even VNC managed to do better. And by moving video, I mean a flash animation like you get in a web page, not DVD quality FMV. The screen update code is nothing short of appalling; quite often a webpage is unreadable because the *entire* screen is updating to display one lousy Flash advert, and I've even seen mouse rollovers on links cause this. Whatever happened to atomic updates? While I'm slating the Citrix code, lets take a look at some of the other issues I've had the misfortune to experience:

• One random key stops working in one application session and nothing short

Re:A couple of considerations

[Zocalo]

Ever tried applying patches to 1000 dumb terminals, oh... right... you won't ever have to.)

Ever had to flash the damn firmware on 1000 dumb terminals, because the vendor made a coding error? Better yet, ever tried doing all that when a power failure during the upgrade processes requires an RTB repair because of the lame implementation?