Making Mouse Wheels Work w/ a KVM?

Elvii asks: "My mouse wheel doesn't want to work through my KVM. It doesn't work in X11 under Linux (Debian 3.0, kernel 2.4.20), but it works in Windows on same machine, through same KVM, so that tells me it's a protocol or driver issue , which is beyond me. I have no other OS's to test on, although I read online that FreeBSD can handle the mouse wheel in this type of setup. When I set the mouse type to IMPS/2, it just twitches in corner and randomly clicks. Anyone know if it's a kernel issue or an X11 issue? I've googled and found nothing of real use there - just that some KVMs work and some don't. Plain PS/2 works but I want my wheel too." The kicker is that when the mouse is plugged directly to the machine, the mouse wheel works just fine! Has anyone else experienced the problem? What did you do to fix it?

USB

[DeadSea]

USB has allowed me to give up an expensive KVM. All the computers in my rack now have a couple USB ports.

1. Get a USB keyboard with a built in hub (~$50)
2. Get a USB mouse with a scroll wheel (~$30)
3. Get a USB switch (~$20)
4. Plug Each of your computers into the switch's outputs
5. Plug your keyboard into the switch input
6. Plug your mouse into your keyboard

For less that $100 you won't have to by an expensive (up to $500) KVM.

There are a couple drawbacks:

1. I don't know of a USB monitor, so you will need a different monitor switch.
2. Because this actually disconnects your mouse and keyboard from the computer, they may take a few seconds be be recognized by the computer and start working when you switch

You can get monitor/usb KVM switches, I don't know how much they cost, but the scroll wheel will probably work just fine though them as well.

What is this?

[termos]

Okey, what is this? Isn't this the sort of question you usually ask in a discussion forum or even IRC? I don't see why someone whould make a slashdot article over it. I did a search on google and found many resources for how to fix this, take a look here [koala.ilog.fr], here [freebsd.org] and here [linuxquestions.org]. And if you want to browse the results yourself, here [google.com].
I've googled and found nothing of real use there.
I don't have a device like this myself, but from the results I got I'll say it looks quite useful.

I've got 3 Belkin KVM's with the same problem

[ComputerSlicer23]

I've got 3 maybe 5 if you count the ones at work that have exactly the same problem. I've got two of the entry 4 ports, a 2x8 matrix stacked with another 2x8 matrix, and a 4 port pro from belkin. All of them have exactly the problem you describe under Linux (various flavors of RedHat).

There are two things to check, first turn off gpm. It's never done anything but give me grief in all the time I've ever seen turned on. I know that this will solve problems on several different KVM's I have. I know on one of the KVM's, it fixed all my problems so I could use the IMPS driver without doing the second fix.

Second, is that something is completely screwed about XFree86 of handling the PS2 mice, you can switch to a serial mouse, but no wheel then. The way to fix the problem, is to get XFree86 to resync/reset with the mouse. After switching from once machine to the next, immediately switch to a virtual console, then back to X, and the PS2 drivers will resync/reset/"do the magic to make it go". I've got no idea what the problem is, or why switching consoles works, but on the various Belkin Switches I've seen that is the fix that works best.

Kirby

Here's my take

[MrResistor]

Most modern KVM switches will send a signal that tells the machine that it has a keyboard and mouse plugged in even if you're actually switched to another machine. My guess is that the KMS' pseudo-mouse is just a basic 2-button, so Linux doesn't recognize that it's actually a wheel mouse that's plugged in. Have you tried booting the Linux box completely while switched to it (meaning you don't switch to another box to do something else while it comes up)? That might make a difference.

Also, check for the ZAxisMapping option in your X11Config (you may have more than one, and the one in /etc might not be the one being used), and/or you might try installing imwheel, which is supposed to fix some mouse wheel in Linux issues. I would probably do both.

Re:What is this?

[slashkitty]

None of your posted links have any solutions. I'll save everyone the trouble of reading all those links.

Link 1: Unfortunately, there does not seem to be a remedy at the moment.

Link 2: I never found a way to make the wheel work without buying a different switch.

Link 3: Was about a Different switch

Next time you post links, don't assume they have meaning full information just because they mention a config file.

linksys tech support

[linuxwrangler]

I have no problem at all with my Logitech wireless optical wheel mouse running through my Belkin 4-port switch.

Did you bother with the Linksys support site? Perhaps this [linksys.com] is the problem you are having.

The Linksys product description says, "Because they donâ(TM)t use software, the ProConnect Compact KVM Switches are compatible with all major desktop and note-book computers." One might read into that statement that the switch is not altering the electrical signals and that the switch is compatible with all mice. Sadly, that appears not to be the case and although a known limitation they don't mention it in the description. I'd send it back and buy from a company that makes KVM switches that work properly.

Similar issues

[nocomment]

I've had similar issues with belkin LVM's working with OpenBSD. Turned out to be a PASSIVE kvm and what I really needed was an ACTIVE kvm. The difference for those that don't know is that the active maintains a signal to the mouse port in effect "tricking" the computer into thinking it was never switched away, whereas passive kvm's will just switch it away and don't really care if the OS notices.

Re:What is this?

[Jeremy Gray]

The point you're missing is that none of the links give an actual solution to the problem. The three best solutions so far (from my research) are:

• try a different KVM
• reset the X mouse driver with some script or program that outputs the appropriate reset code to the mouse device
• reset the X mouse driver by switching to a virtual console and back

And while the question is phrased as if it should be posted to comp.os.linux.* or somesuch, the underlying issue is valid. The Windows mouse driver is able to compensate for shortcomings in KVMs, while the various open source drivers are not, despite theories that this could be done in the X mouse drivers. There is no solution and no good workaround, so hopefully publicity will inspire someone to find the solution.

The Fix for Me

[Jebediah21]

Mouse wheel support works for me under Linux, but if I switch to another machine with the KVM it will kill the mouse wheel support. It is something about X and the switch (can't remember the details). Try hitting ctrl + alt + f2 or something to goto a new login screen without X before switching to another machine. When you come back to the Linux box do ctrl + alt + f7 to get back to Linux and your mouse wheel should work.

Re:USB

[njchick]

4-port USB+Monitor switch for $78.94 [sparco.com], thanks to Froogle [google.com]

Re:I've got 3 Belkin KVM's with the same problem

[bluephone]

you can switch to a serial mouse, but no wheel then.

Sure you can. My first wheel mouse was serial. I have 3 of them in a bin. Look here [google.com].

IO Gear

[Futurepower(R)]

IO Gear KVM's work fine.

multi input monitors with USB port switch built in

[Splork]

The Mitsubishi DiamondPro 900U (diamondfoo, whatever) has a built in usb hub and two usb upstream ports that it switches between when you switch between the BNC & VGA inputs via the simple button on the front.

only works for a two systems; but if that's all you need this is seriously convenient.

better hope windows doesn't whine about "you unplugged a device without asking me first" though. don't put anything other than your keyboard/mouse on its hub.

and kiss some chance of configuring your BIOS goodbye as many BIOSes won't support USB keyboards connected to a hub (this is a bios not being usb compliant problem). better off having a real keyboard on hand for bios config.

Re:Here's my take

[AndyBusch]

Ack! Imwheel is an ancient crutch. Any reasonably modern software understands the wheel directly. And anyway, if you don't have ZAxisMapping set up to begin with, imwheel won't help.

Probably, you just got a bad KVM. My IOGear chugs along happily.