Virtualize Terminal Server

[techie08]

We have a windows server setup that is used as a Terminal Server and for staff VPN Connections and i wanted to know if this would be fine to virtualize in VMware ESX?

 

Thanks

[Netman]

We have done this with 2 Windows Server 2008 TS boxes and have had no problems. Even though it's not 'officially supported', as long as you have decent hardware specs I don't see why not.

[Butuz]

Yep - waiting on funding for new servers and will be virtualising all 3 of my terminal servers onto Citrix Xen. Be aware that virtualising terminal servers onto Xen/Vmware does have a performance overhead (i will be testing this to get exact figures), you may not be able to fit quite as many clients per server as you could before virtualisation but as long as you build this into your plans and possibly spec up your servers a bit - the benefits faaaaaaar outway the slight performance drawback.

 

This is done alot in industry. My mate has hundreds of virtualised terminals servers on Vmware ESX serving thousands of users across the world - he is moving to Xen because of increased perfomance. He's currently fitting 60 TS users per Tserver virtualised with Xen and he loves it. (I think if i recall he was fitting 50 users per server on Vmware)

 

Butuz

Edited May 1, 2009 by Butuz

[budgester]

Hold on I don't get this at all.

 

How many clients can you get on a Terminal Server ? is there a limit ?

 

Lets say you can get 30 clients on your current Terminal Servers, and you have 3 terminal servers.

 

Now you want to virtualise all three of them Terminal Servers so you go out and buy a BIG server.

 

You now have a server that can either run

 

1 Terminal Server OS

Terminal services for 90 clients.

 

or

 

1 Host OS

Virtualisation Software

3 * Terminal Server OS

Terminal services for 90 clients

 

Unless you are using ESX to migrate the virtualised servers to under utilized hardware on a dynamic basis then you are taking a performance hit straight away.

[localzuk]

Hold on I don't get this at all.

 

How many clients can you get on a Terminal Server ? is there a limit ?

 

Lets say you can get 30 clients on your current Terminal Servers, and you have 3 terminal servers.

 

Now you want to virtualise all three of them Terminal Servers so you go out and buy a BIG server.

 

You now have a server that can either run

 

1 Terminal Server OS

Terminal services for 90 clients.

 

or

 

1 Host OS

Virtualisation Software

3 * Terminal Server OS

Terminal services for 90 clients

 

Unless you are using ESX to migrate the virtualised servers to under utilized hardware on a dynamic basis then you are taking a performance hit straight away.

 

If you're running a 32bit terminal server, yes there is very much a limit - we hit about 25 before major slow downs due to memory limitations.

 

If you're running 64bit terminal servers then no, i don't understand virtualising them.

 

If you have a server which has 16Gb of RAM, and you only use a 32bit OS, you're effectively only using 1/4 of it's capabilities - so virtualising will mean being able to fit at least 3 (if you say the last bit is for overhead/lost performance) 32 bit servers on one server. etc...

[CyberNerd]

 

If you're running 64bit terminal servers then no, i don't understand virtualising them.

 

 

only for ease of management, etc.

 

we run 2 X 32bit 2003 guests in 8Gb server. seems to work well.

probably a bit of a performance hit compared to running 2 32bit physical servers, but they are easier to manage so what the heck.

[budgester]

only for ease of management, etc.

 

we run 2 X 32bit 2003 guests in 8Gb server. seems to work well.

probably a bit of a performance hit compared to running 2 32bit physical servers, but they are easier to manage so what the heck.

 

So for the virtualisation to work well, you need to have a 64bit base OS, with 32bit guest OSs, otherwise you will still run into the same memory issues.

 

And what is it that you can't do on a 64bit os that you can on 32bit.

 

And if you had a 64bit server why wouldn't you want to run the thin clients on 64bit if you could.

 

And surely then its gotta be easier to run 1 physical server that can manage all the clients rather than a VM server with 2 guests.

 

Plus you've got the network bandwidth to take into account.

 

I could understand if you had Two host servers each with a guest TS, then if one failed you could transfer the guest to the other host while you are waiting for replacement hardware.

[localzuk]

There is a good amount of educational software which refuses to run on 64bit, some because it is 16bit and some because it is poorly written. So 32 bit OS's are required for that really. Not many people have moved to 64bit TS yet, as this would mean having to use Windows Server 2008, which is still quite new. 64bit windows 2k3 has poor support for 32bit apps.

[CyberNerd]

So for the virtualisation to work well, you need to have a 64bit base OS, with 32bit guest OSs, otherwise you will still run into the same memory issues.

yes, but most/all base os's are 64bit

 

And what is it that you can't do on a 64bit os that you can on 32bit.

 

And if you had a 64bit server why wouldn't you want to run the thin clients on 64bit if you could.

run old crappy 16bit apps?

for us it's just more hassle to test it all and migrate when we've got a perfectly good 32bit system.

 

 

And surely then its gotta be easier to run 1 physical server that can manage all the clients rather than a VM server with 2 guests.

 

I dunno about ms virtual servers (most likely they are a pita to manage - like most ms products) but citrix has some pretty good management tools to manage multiple servers. I see our server farm (12 servers) as just lots of redundancy.

To commission a new virtual server takes about 2hrs by rebuilding from an existing server using esxi tools. a new physical server can take ages.

 

Plus you've got the network bandwidth to take into account.

 

honestly, it's tiny amounts of bandwidth on a terminal server

 

I could understand if you had Two host servers each with a guest TS, then if one failed you could transfer the guest to the other host while you are waiting for replacement hardware.

 

yes, that's the idea - we just run two or more terminal servers on each physical.