Just a reminder: with Terminal Server and Citrix, the issue is more a matter of latency (i.e., ping times) than bandwidth. You could have a fast connection at your end, but if it's a long distance (say, trans-oceanic), your ping times could still suck. Under 100 ms is ideal, over 200 is noticeable, over 500 is starting to get pretty bad.
A 128K ISDN connection typically has sub-50ms ping times and can realistically handle 10 to 20 users depending on real-world activity. A T1 from Florida to Alaska could be unusable. Bandwidth needs really depend on actually user and screen update activity. Latency issues, however, will show up with a single user. Test. The place you'll see most problems is in keyboard response when typing. Terminal Server sessions don't actually send and receive a lot of data -- but there's several times more going TO the users than FROM them, so you need to look at you server's upload speed. Citrix has some optimizations that can improve both bandwidth and latency issues, but in my own non-exhaustive tests some time ago, I didn't see major benefits. I used to avoid running serious Terminal Server connections over the Internet due to quality control issues: you never know from one minute to the next exactly how it's going to be routed, and what hop might get overloaded. Tracking down causes... don't waste your time. I still prefer private circuits if I have a choice, and the latency tends to be a lot better. One other point: I definitely think you should be running more than one server, for reliability. Terminal servers are multi-user PCs. Users mess up their systems (lock them down as much as possible) . You will be fixing user problems, rebooting, etc. Being able to shut down one server while users work on the other is a very good thing compared to everything going dark at once. Especially if you have load balancing and roaming profiles. /kenw From: Phil Guevara [mailto:[EMAIL PROTECTED] Sent: February-20-08 1:36 PM To: NT System Admin Issues Subject: RE: Virtualize Terminal Server or not? Andy, Do your users access TS across the WAN? and if so, what type of bandwidth do you have? Thanks for your help. Best, Phil ________________________________ From: Andy Crellin [mailto:[EMAIL PROTECTED] Sent: Wednesday, February 20, 2008 1:26 AM To: NT System Admin Issues Subject: RE: Virtualize Terminal Server or not? We are running TS virtualised on ESX with about 40 users and its running fine. They are reasonably well specified, with the 2 hosts being ProLiant DL380 64bit dual quad-core + 16Gb memory and each VM having 2Gb memory and a single core to play with. We also use 2X to load balance. I don't use the facility myself but my colleagues tell me that they and their users are happy with the response. Andy Crellin Technical Services Manager Leonard Cheshire Disability Telephone: 01904 479200 E-mail: [EMAIL PROTECTED] From: Phil Guevara [mailto:[EMAIL PROTECTED] Sent: 20 February 2008 00:34 To: NT System Admin Issues Subject: Virtualize Terminal Server or not? Anyone know if it makes sense to virtualize a core terminal server that will have about 50 concurrent users connecting to it? Or is it better to get a new server that will be dedicated for this purpose? Best Regards, Phil Internet communications are not secure and therefore Leonard Cheshire Disability does not accept any liability for the content of this message. Any views or opinions presented are solely those of the author and do not necessarily represent those of Leonard Cheshire Disability. If you have received this transmission in error, please contact the sender and delete it immediately. Leonard Cheshire Disability is a company limited by guarantee, registered in England no: 552847, and a registered charity no: 218186 (England & Wales) and no: SC005117 (Scotland) VAT no: 899 3223 75. Registered office: 30 Millbank, London SW1P 4QD. ~ Upgrade to Next Generation Antispam/Antivirus with Ninja! ~ ~ <http://www.sunbelt-software.com/SunbeltMessagingNinja.cfm> ~
