From: "Julian Price", Wednesday, April 22, 2009 3:46 PM

I use RDP because it allows copy & paste of text between the local and remote machines. VNC does not, unless I've just not got it set up right.

• Julian

Most of my users are not sophisticated enough to handle mixing remote and local modes. I'm expecting to turn the remote machine into a thin client equivalent (enabling me to move the WinXP license to the VM).

This seems to reduce some of my potential support issues.

I'm currently experimenting with Thinstation (thinstation.net). There are a couple of issues with it, like sound, but I'm leaving those issues for later.

On 04/27/2009 12:17 PM, Kai Schaetzl wrote:

Julian Price wrote on Wed, 22 Apr 2009 22:46:44 +0100:

...

I use RDP because it allows copy & paste of text between the local and remote machines. VNC does not, unless I've just not got it set up right.

I have always been doing that (copy text to VNC). I run VNC for my Windows *hosts* rather than RDP because I can attach to an existing console session and not logout the console. RDP doesn't attach to a session but opens a new one.

With rdesktop you can also leave the session running and reconnect to it.

From: "Joseph L. Casale", Wednesday, April 22, 2009 4:23 PM

...

I'm experimenting with using WinXP Xen guests as an alternative to upgrading workstations. The administrative advantages seem overwhelming.

Using the beta opensource parvirt drivers? Performance would be unacceptable otherwise. On that note, my environment would not permit the unstable nature of such an exercise...

Actually, no. I'm using the fully virtualized guest. My test virtual machine server is a Dell PowerEdge 2900 with dual-core Xeon with stock CentOS 5. It only runs at 2Ghz, but I'm finding acceptable performance for the standard business applications that my users will run. The system can go up to 2x4 core Xeons running at 3.33Ghz or something. Ram can go up to 48G and it has the option of 2 banks of 4 slots for hotswap hardware RAID. I'm hoping to be able to run about 12 virtual XP boxes on a 2900 with 8 x 3Ghz cores and 16G RAM.

My current workstations are 1.6Ghz Celerons with 512M to 1G RAM. They are only running Outlook Express, Internet Explorer and a couple of proprietary applications.

If paravirtualization drivers for WinXP ever become stable, that'd improve performance and probably increase the number of WinXP VM's quite substantially.

...

Please share thoughts about using VNC vs RDP for remote desktop connections.

RDP will be way faster, not to mention using vnc provides access to the console which won't have video performance needed.

Have you done any real world like testing? My experience seems to indicate VNC being faster on a LAN. Since the console is being redirected in the host, rather than the guest, it seems to demand less processing power. Also, turning off remote access in the guest loads less software. Since the host supports the VNC console access, it becomes available much sooner than WinXP get termserv up.

...

Please share any anecdotal information regarding user reactions and/or implementation issues.

There's nothing cooler than Xen, but IMHO opinion I would be using something a bit more stable for Windows guests, it's not the right tool for >this< job as far as I am concerned.

YMMV

I've got some local databases with chatty Windows clients that becomes unuseable across the WAN and doesn't play well with MS Terminal Services. Rather than have a stack of physical WinXP machines for my remote users, I'm looking at virtualization. VMWare gets too expensive, too fast.

From: "Christopher G. Stach II", Wednesday, April 22, 2009 5:31 PM

It's a really bad idea to allow connections into dom0 from anything other than an administrative network and for administrative purposes. RDP is generally a better solution than anything else, anyway.

I don't think anybody disagrees with this, in theory. But I'm not going to kill the project if the expected performance is less than required using RDP and acceptable using VNC. Since I'll have a hot spare and the virtual machine server is relatively easy to rebuild, I'm going to have to allow for it as a Plan B.

From: "Manuel Wolfshant", Wednesday, April 22, 2009 4:58 PM

...

• XP was MUCH faster in Xen, compared to real hardware (!)

I've been pretty happy with the performance, as well.

• RDP beats VNC in terms of speed any time, any place. I cannot evaluate

precisely the factor, but empirically I'd say that in our conditions (WAN link, 6 Mbps upstream link on one site shared with other projects, 100 Mbps on the other site) it was at least 2-3 times faster.

Interesting. Thanks.

• rdesktop ( the linux app) is really cool, as it allows you to

share/transfer local resources to the remote XP session (for instance you can map a local directory as a remote networked disk, without the hassle of passing via Network Neigh.). VNC forces you to either explicitly map such resources (hence you would also need something like samba on the linux side) or use scp.

Either way, I won't be having local resources. Trying to keep it simple.

• the only problem with RDP is that by default Windows limits the number

of simultaneous connections. but patches do exist (which violate the licensing/usage terms, so beware).

I am interested in the multiple connections allowed with VNC for support type console sharing. When connected with RDP, the console of the VM has a login screen, so you can't use VNC to the console at the same time as a RDP connection...

As of implementations issues .. I had two (or should I say three?) problems:

• one is detailed in an older thread on this list ( look for "Using the

parallel port from domU", 02/02/2009).

My printers are all network printers, yay!

• second is due to Xen creating a large file with the same size as the

disk given to the VM. I would have believed that sparse files would have been used, but df showed the opposite. I have seen 20 GB of space allocated, despite XP only using less than 5.

I think I've got the VM's setup with sparse files. An ls shows the 10GB size, but df doesn't show all the space in use. However, this is a minor issue. The virtual server I'm looking at has the capacity for a couple of terabytes of hardware RAID storage.

• last issue did not occur with stock Xen but with v3.3: Java inside the

VM went nuts and starting consuming 99% of the processor.. while doing nothing. Once we reverted to stock Xen from C5.2, it went back to normal.

I'm going to be trying to avoid using other than stock Xen. This has got to reproducible and supportable. I'm thinking of setting up a local repo to prevent automatic updates from breaking anything.

Thanks for all of the information. Makes me wonder what happened to eliminate the need...

From: "Christopher G. Stach II", Wednesday, April 22, 2009 5:39 PM

You can handle this with Thinstation and many other thin clients.

Thinstation is exactly what I'm currently using.

On 04/23/2009 02:19 AM, Ed Heron wrote:

...

• rdesktop ( the linux app) is really cool, as it allows you to

share/transfer local resources to the remote XP session (for instance you can map a local directory as a remote networked disk, without the hassle of passing via Network Neigh.). VNC forces you to either explicitly map such resources (hence you would also need something like samba on the linux side) or use scp.

Either way, I won't be having local resources. Trying to keep it simple.

Well, if you can implement a LTSP-like solution, good for you. In my case all users already had local linux workstations running C5, the XP was needed only for a couple of proprietary applications and for a limited period of time. The problem came from the fact that despite using what I call pretty decent hw, most of the users did not have hardware capable of doing full virt but we had to start the project really FAST ( The software supplier informed me that the proprietary applications cannot run on linux the very day the project started, despite doing 3 months of preparations for the project). Basically I had no choice but create VMs on a server with spare resources (which happened to be in another city than the users). Your use case is different :)

...

• the only problem with RDP is that by default Windows limits the number

of simultaneous connections. but patches do exist (which violate the licensing/usage terms, so beware).

I am interested in the multiple connections allowed with VNC for support type console sharing. When connected with RDP, the console of the VM has a login screen, so you can't use VNC to the console at the same time as a RDP connection...

It's not really like you describe it. With the proper patch, several different RDP users can share the VM, just as an 2003 server would do for more money. In our case, this was important because - at least in the beginning of the project - the number of simultaneous users exceeded the number of available VMs As of VNC sharing the console .. I am not sure what are you speaking about. As far as I know, VNC is quite reluctant to share a single desktop with several users, unless the connections are R/O. And in a LAN the speed is acceptable, but via remote links VNC quickly becomes "unpleasant". If you go the VNC way, I strongly suggest to examine NX instead.

...

As of implementations issues .. I had two (or should I say three?) problems:

• one is detailed in an older thread on this list ( look for "Using the

parallel port from domU", 02/02/2009).

My printers are all network printers, yay!

I have only networked printers, too, but in this case it was not about a printer but a hardware toy (ASIC development board).

I am interested in the multiple connections allowed with VNC for support type console sharing. When connected with RDP, the console of the VM has a login screen, so you can't use VNC to the console at the same time as a RDP connection...

Remote Assistance parallels the behavior you're after with RDP.