Hi,

This is my first time posting to this forum. After reading messages and replies, you all seem to be easy people to communicate with.

I have read many of the kvm posts on here and sadly find we are all having the same problem--incompatibility between the usb kvm and the linux box. I tried the belkin omniview dvi with usb and audio 2 port box and found it to be painful as others have mentioned. I just tried the avocent 4 port dvi with usb and audio kvm box and I like many things about it. Unfortunately, it doesn't recognize the mouse or keybd when switched to the linux box. Keybd and mouse plugged directly into the linux box (bypassing the kvm) is fine. kvm performance with the XP pro machine is quite good. The build quality of the avocent is good.

My system: computer #1--Dell 8400 running windows XP pro; computer #2--HP xw4100 running redhat 7.3 linux (yes I know its ancient--CAD compatibility reasons)using 2.4.18---26xxx kernel I gather. Logitech MX700 optical USB mouse and associated media elite keybd (Y-RJ20)--both devices wireless.

I have tried numerous things to make the linux box work with the avocent and am realizing this may be more of a problem with linux OS or USB drivers in the OS, etc. I am not that swe proficient --I know what kudzu does and have looked at the hwconf file and have seen the messages in /var/log/messages but I am very far from being a heavy duty swe patch kind of guy or any ability whatsoever in installing a new linux OS.

Given the above (and I apologize for the long diatribe) does anyone know of a kvm that will work with my linux box and the mouse and keybd I am using? I am open to ideas that might replace the mouse and keybd to find a switch that works. Or even some simple swe patch to the linux box that doesn't require major ability in that area to install.

Any solutions/ideas greatly appreciated.

Thanks,
jk

I don't have a solution but I will tell you what I now use. I had two computers connected to a belkin kvm switch. It worked in windows and linux but it was not dvi. I decided to pick up another monitor and use Synergy. Synergy lets you share your keyboard and mouse over your lan. Now I have two monitors on my desk and one keyboard and mouse. Synergy works very well and has solved my kvm problems for free.

Thanks for the reply and the idea. I will think about your idea of using synergy. After reading your reply I checked it out--very cool swe! I will definitely consider it. Only drawback is that it still requires two monitors which requires more deskspace which I am trying to reduce. However, I like the fact that it supports multiple monitors allowing for increasing the effective size of the desktop on one computer. Also, simplifies file copy between my linux and XP systems

Thanks again!

More on this behavior...

Perhaps this will give some gurus an idea of the problem and perhaps a fix. I did some more testing..I monitored the /var/log/messages file using the tail -f command (while using a directly connected ps2 wired keybd and mouse). Also, the switch and usb mouse/keybd are connected to the linux box through the usb. Thus, I was now able to see if the linux box saw the mouse and keybd through the kvm by switching the kvm back and forth from the XP machine to the linux machine. I found out it clearly sees the usb devices through the switch and connects and disconnects the in accord with the switching.

Unfortunately, even though the messages file says the linux box sees the usb mouse/keybd through the switch--they are still completely non-functional on the linux box. The same mouse/keybd are fully functional when they go directly to the linux box and avoid the kvm.

So based on the above symptoms does this have something to do with the signals going through the kvm from mouse/keybd being modified or coded in a way the linux box doesn't like? Other reasons and any ideas for a fix?

Thanks

This KVM is on my shopping list after wasting my time with the Belkin. This was posted on linuxquestions several months ago, hope it helps.
BTW, www.newegg.com has the switch !

"Unlike other KVM's that I've used from other manufacturers, which could get "confused" if you switched between Linux and Windows and would force a reboot, this unit just doesn't care what each box is running, and has never failed to successfully switch from one box to another. Current price (March 2004) is about $60. Even if you don't need 4 ports, I'd recommend buying this over a 2 port model anyday, due to its qualify and the fact that more often than not, you _someday_ will acquire a 3rd machine if you haven't already." -- J.W.

Product link: http://www.trendnet.com/products/TK-401R.htm

Scott Nash

Thanks for the reply Scott. Unfortunately, I need a DVI + USB KVM and the one you refer to is VGA + PS2. I looked at other trendnets and from what I can tell none of them have DVI + USB. But I appreciate your help.

Solved it. The IOGEAR KVM worked! At least for the last 4 hours. No video degradation and no detectable keybd or mouse lag. I only tested switching behavior using the mechanical switches on the box. I did not check for hotkey switching since I really don’t need or care about that. The switching takes a few seconds due to the usb. Hopefully it lasts.



The KVM models that work: IOGEAR GCS-1762 (2 port); GCS-1764 (4 port)



Details:



PC 1—dell dimension 8400, windows xp pro service pack 2

PC2---HP xw4100, redhat linux 7.3 running kernel 2.4.18-26.7.x

Peripherals: mice tested: Logitech MX700 cordless USB optical mouse; Logitech corded USB optical mouse: model number M-BT96a

Keybd tested: Logitech cordless USB keybd model number Y-RJ20; Logitech corded USB media elite keybd model number Y-BN52

Cables used: avocent 9 foot set of dvi/usb/audio cables (about $25 per set on amazon)



Cordless mouse and cordless keybd tested together. Corded mouse and corded keybd tested together. Key finding: cordless set up ONLY worked when the usb cable connected to the front mouse port (not to any other console port). Corded setup only worked when connected to mouse and keybd front console ports. Using the rear peripherals didn’t work in linux and created doubled keystrike effects in XP. Other mice and keybd’s may work –these are the ones I tested. I recall calling IOGEAR tech support before buying them and asking which mice and keybd’s they support. Their answer: we only test for our own IOGEAR brand of mice and keybds. A quick look at their keybds and mice made me certain they are simply repackaging/renaming Logitech equipment. Somehow I am not surprised. I already use Logitech so it made me feel it was worth a shot.



Build quality is decent. Solid metal enclosure (unlike cheap plastic belkin for same price!). Comes with all cables inside box but I already had the avocent hooked up and I like the avocent cable quality better. They are also longer (avocent is 9 ft and IOGEAR is 6 ft) and therefore more flexible for setup connection. Although there seemed nothing wrong with the IOGEAR cables except for a stupid mechanical issue they created for themselves: In the attempt to simplify cable connections and keep each pc’s cables together they decided to meld the cables together into one thicker cable and didn’t quite plan the cable tensions and lengths of usb vs. audio vs video in a given set correctly so their can be significant pull on the cables and/or they may be a hassle to connect.



The unit gets a bit warm so it needs to have enough airspace to keep cool.



Key caveat that you probably know: The KVM needs to be switched to the channel that you are rebooting/powering up or else it can lose synch on video among other possible nasties.



After all of the effort this search took (3rd kvm tried), I hope the above helps someone else avoid the pain this kvm stuff can be.

Jon