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WinVNC vs. KVM Extender?
systmc asks: "I'm trying to decide between using WinVNC or a KVM extender at a customer's site. I'd like to use WinVNC but I'm concerned about it's CPU usage on a WinNT system (with an inactive client connected CPU usage was at around 8%, even with Raw encoding. PCAnywhere was about 0.5%). Does anyone have experience tweaking VNC? If hardware winds up being necessary, what KVM Extender would you recommend?"
Have you tried TightVNC? I don't know about it's CPU usage, but IMHO it is much better and faster than normal WinVNC. It can also do JPEG-encoding on the picture data, so it is really bandwidth-efficient.
This is the place where you write something that will make you seem like a complete idiot.
You haven't explained why you want to use a remote machine.
If it's to run applications, then the WinVNC/PCAnywhere/etc route is a good one. It's more flexible, because you don't need a cable. You can share the machine between more than one person, and you don't need extra hardware.
Personally, for remote administration, I'd always use the KVM extender solution. If the machine that you're administrating isn't behaving, then the remote control software probably isn't working properly either. Remote software doesn't let you watch bootup screens, or reconfigure the Bios.
So, before you make a decision, I think you need to look carefully at the purpose of the solution.
What kind of machine is it at the client's site? If it is W2K you could use rdesktop. This is apparently a fairly chatty protocol (compared with Citrix at least) but it is probably more CPU efficient.
However, as another poster said, I think the KVM is the way to go, for the same reasons.
The old Timbuktu does a decent job. I have a client that's moved a number of their machines over to that to replace pcAnywhere. They feel it's faster and has less impact on the remote machine. I believe it gives you something that pcAnywhere doesn't have: you can have multiple clients connected at once as long as at most one is in Control mode (vs. Observe mode).
Make sure you don't have "poll entire screen" checked. It's a pig.
My personal setup is TightVNC with everything BUT "poll entire screen" checked. It's pretty zippy, even over dialup, so long as you aren't redrawing the entire screen.
Perhaps a better (and more professional) solution is something like Citrix. VNC limits you to one connection at a time, while Citrix allows multiple sessions simultaneously. In addition, Citrix is probably the fastest VNC-style thing I've used, and the Metaframe protocol works reasonably well, even over a modem. It's also more secure - rather than a VNC login, you use your Windows login, just like it's local (except it isn't). It's about the closest thing available for Windows to a remote XDM.
But I agree : vnc is a lot more efficient on *NIX that on NT...
And as for security, someone mentionned, there is not so much encryption with vnc. At least, the vnc password is not sent in cleartext on the wire, but after that every keystrokes goes as it is into an udp packet.
But I'm using VNC through a VPN tunnel to work from home, and since the generated network traffic is relatively light-weight, it's working pretty well to control *NIX-based hosts...[Pruneau
If you happen to have Compaq servers check out their Lights Out Management boards. They are almost a complete PC on a card. Intel i960 CPU, RAM, ATI Vid, and a NIC. They let you completely remote control the system through a web browser. It has its own power supply so you can restart the system and follow it through the POST test and everything.
Pretty slick. They are $499. I put them in all new servers now.
I cannot understand why people talk about WinVNC, Proxy, PcAnywhere etc. Just use the included NetMeeting and enable Remote Desktop. I have it on all my servers and it's fast enough for me. Everywhere I go computers have NetMeeting installed (included in Windows) so you can call the servers. NetMeeting have encryption and uses normal NT accounts for users/password (or Active Directory/domain admins).
Believe me! I've tried them all! (winvnc, tightvnc...)
BTW: Don't forget to lower your colors (256color desktop. it's faster).
We also connect all of our AutoViews with a Cybex LongView. Basicly your KVM extender. You can use the LongView with almost any KVM system you already have install. We have them connected to Belkin KVMs. The extenders sends their signal over a standard ethernet cable.
WARNING - Don't ever patch the ethernet cable through a switch. You will kill the switch. But you can send the signal through a normal patch panel, if you wanted the LongView receive to be at your desk. I am not sure of the distance for the extender, but all in all they work really good.
Oh, I just looked. Cybex is now called Avocent.
ks
It's not any less CPU-intensive on the host, unfortunately.