On Mon, Jun 4, 2012 at 3:45 PM, Harry Putnam <rea...@newsguy.com> wrote: > Stroller <strol...@stellar.eclipse.co.uk> writes: > >> On 1 June 2012, at 09:33, Harry Putnam wrote: >>> ... >>> I am running thru a kvm switch, but don't really have the option >>> without a fair bit of juggling to try it with everything hooked >>> direct. I have tried plugging a keyboard direct, with no result. >> >> I don't really understand. You can't try direct, you tried direct. Which? >> >> KVMs are just flakey sometimes. > > Perhaps if you consider that KVM is a switch that controls several > components, (keyboard, Video and mouse) it will come to you.
Back when my KVM was just a mechanical switch that flipped between A and B, and only switched VGA, a serial port and a mouse, that was true. For years, though, KVMs have tended to man-in-the-middle USB keyboards and intercept key sequences in order to control switching behaviors. Being the man in the middle is _very_ tricky, and it's highly unlikely kvm manufacturers get it perfect. At the very least, it's still intercepting keystrokes, which means that your input is either funkily jittered as it buffers looking for a combo, or it means that your input is incomplete. I'm not saying that the KVM is necessarily the source of your problem. I'm saying it's a far more complex device than you envision it to be. > > You are at liberty to plug a second keyboard into a USB port. I have > done that under certain condition in the past and did try that > unsuccessfully, as reported, this time. Makes sense. > >> >> As discussed at: >> http://www.gossamer-threads.com/lists/gentoo/user/223068 >> http://comments.gmane.org/gmane.linux.gentoo.user/252806 >> > > I'm not buying the idea that flakyness rules with KVM. There may be > flakyness BUT based on my own experience of yrs of KVM use running > gentoo, debian and few tries at a few other distros... always with a > kvm, and currently am running debian on one of the other kvm boxes on > my current setup. > > I should be quite a good test case. Someone, not all that bright, nor > very competent and yet I've been able to run linux, windows and > solaris all on various KVMS for a period of several yrs.... I'd guess > at least 7 yrs. > > There were problems from time to time but none that prevented me > continuing to run with a KVM after a pause, sometimes a good one > to get things working. I get it. You fancy yourself an expert on KVMs. Do you realize that KVM hardware is liable to be around as diverse as GPS and serial dongle hardware? That's pretty significant. > >> I'm inclined to agree with Hinnerk - if the keyboard is recognised >> by BIOS then it's Linux problem > > I hope so too, that would be nice. Seems likely, given that you tried plugging the USB keyboard in directly without the KVM connected to a USB port. (You did, didn't you?) > >> >> However, if you're having keyboard, video or mouse problems and a KVM >> is in the chain then you *always* remove it as the first step. > > No that is not the case. As indicated in OP, there is NO mouse > trouble. "keyboard, video _or_ mouse problems." And he's been trying to offer you advice on diagnostic procedure. And the advice makes sense at its core; simply the system as much as possible, then add pieces back until something breaks. The more you grant utmost confidence or assumptions about a component or behavior, the more things boil down to errors you think were "impossible." > >> Don't come to us saying "I have this problem and just to confuse the >> issue it could be the KVM" (something we're unable to help with), >> instead say "I originally tried with a KVM, but having removed it, >> that makes no difference". > > I guess you've been elected to the post of Sargent at arms in my > absence. Here, again, he tried offering you advice on how to present your problem in the clearest way possible, maximally avoiding confusion, and you've only taken offense. [snip irony] > ------- --------- ---=--- --------- -------- > > Maybe someone, will still read my query and give it some thought. > > My idea starts with the premise that it ain't the KVM. For certainty's sake, have you tried plugging the keyboard in directly without the KVM plugged into the USB port? I don't think it's particularly likely that the problem is the KVM, either, but I do see it as a plausible source of interference if both devices are plugged into separate ports. USB normally handles multiple USB keyboards just fine, but I don't know how your BIOS's 'legacy' support handles it, and there have been rumblings in areas of multi-user workstations lately, so it's plausible things are changing. And, again, there's the potential of the KVM having a faulty implementation of USB HID proxy behavior. > > Because some users are livid as to how faulty KVMS are does not make > that the problem here. (Again, nobody was trying to pin the blame on the KVM, they were trying to verify that the problem _wasn't_ the KVM). > > In this case it would take a fair bit of diddling around to do a > direct hook up since the kvm is DVI based and I'd need an adaptor I > don't have (other than the one built into the KVM cables). We get it; removing the KVM completely from the loop is a PITA, and you've convinced yourself it's not worthwhile. I assume it has multiple USB plugs, one for each upstream computer. Can that KVM power itself from a USB port other than the one it's currently passing keyboard input to? (I assume so, or you'd have to work around state loss issues when switching between upstream devices.) > > OK ------- --------- ---=--- --------- > > Now this whole problem may have taken care of itself in an unexpected > way. > > My niece, for whom I'm building this machine has informed me today > that she really really hates trying to run linux and wants to get on > with her work with tools she knows. > > Exit the gentoo install, enter an old XP disc I'm now trying to > install. You chose the just about the absolute worst distro I can imagine for a Linux newbie to have to cope with, and you gave a spectacularly poor demonstration of setting it up. Technical hurdles happen, but with Gentoo they really hurt when they do. For your niece, I would recommend the LXDE variant of Ubuntu or Debian; it has a look and feel very similar to Windows XP...right down to keyboard shortcuts. > I am sorry for the line noise but it still may come to it that I end > up bringing that problem here again. [ad hominem trolling snipped] Incidentally, the BIOS setting you were probably looking for is either "USB Legacy Keyboard" support, "USB handoff" or "OS Supports USB". Something along those lines. Depends on the BIOS manufacturer and the age of the system. And probably other things. -- :wq
