Live data from Hacker News

The Peculiarly Quiet Decline and Fall of the KVM

loper-os.org

61–70 of 145 posts

Re: The Peculiarly Quiet Decline and Fall of the KVM

#61
This tone of this article is pretentious and just plain douchey. The author is largely assuming that their small niche (and petty) use case is what everyone who uses a KVM would want (i.e. using a 4k monitor). The single largest use for KVM is for servers, who the hell is wasting money on a 4k monitor for their servers? There are plenty of reliable and affordable KVM's that the author deems as old relics that work just fine for the large majority of consumers.

Re: The Peculiarly Quiet Decline and Fall of the KVM

#62
post #58
post #53

Earlier quoted context omitted.

I leave my PC running 24/7 pretty much, so at night I want the monitors turned off so it doesn't illuminate the whole living room (which I can see from the bedroom - it is a small apartment). I used to turn them off with the button on the monitor (when all my monitors were DVI), so if the mouse was moved by accident during the night it wouldn't wake the monitors up. Right now I have to let it go to sleep normally, an…

Every monitor I've owned since the early 2000s will switch itself off (or at least go into a standby state where the screen is entirely off and there's a tiny blinky LED indicating that it's still powered) after a period of inactivity. I know some monitors never give up waiting for a signal but at this point maybe it'd be simpler to treat yourself to a new monitor? Edit: Oh, you're talking about things waking your co…

In my experience, Windows 10 seemed to have issues with the "Wake on USB" setting about 6-8 months ago. No matter if I let my computer hibernate or forcibly sleep my computer, it would turn on within 20-30 minutes of me being away. No matter what settings I set, this would happen constantly.

Re: The Peculiarly Quiet Decline and Fall of the KVM

#63
post #58
post #53

Earlier quoted context omitted.

I leave my PC running 24/7 pretty much, so at night I want the monitors turned off so it doesn't illuminate the whole living room (which I can see from the bedroom - it is a small apartment). I used to turn them off with the button on the monitor (when all my monitors were DVI), so if the mouse was moved by accident during the night it wouldn't wake the monitors up. Right now I have to let it go to sleep normally, an…

Every monitor I've owned since the early 2000s will switch itself off (or at least go into a standby state where the screen is entirely off and there's a tiny blinky LED indicating that it's still powered) after a period of inactivity. I know some monitors never give up waiting for a signal but at this point maybe it'd be simpler to treat yourself to a new monitor? Edit: Oh, you're talking about things waking your co…

Disabling wake from USB is not a good idea given I have a USB keyboard and mouse.

Essentially this is a convenience thing, it used to work perfectly fine, then they added HDCP to make things less convenient.

Like I said, I'd be fine if the software (well Windows in my case) has a switch to disable HDCP and restore the old functionality of always assuming there's a monitor there.

Re: The Peculiarly Quiet Decline and Fall of the KVM

#64
post #36
post #9

The main thing that has pissed me off with technologies like DisplayPort and HDMI is that I cannot actually turn my monitors off when I'm not using my computer. With DVI I could turn the monitors off and the desktop and applications would stay where they were. With HDMI/Displayport it considers the monitor disconnected, hence re-adjusts the desktop and moves everything around. I would love an option that I could swit…

There are two possibilities: 1. Fake GPU software, which I haven't researched at all but probably exists 2. Forcing your graphics chipset to turn a specific head on and leave it on Here's a Linux-specific example of how to do #2. Since I'm just talking to graphics hardware here, there should be equivalent operations for all of the following for other operating systems. I don't connect an external display at any point…

>At this point, i3 (my windowmanager) decides to move every single window onto the new offscreen surface area, and I go blind.

Xmonad can't do stuff like this because it treats each monitor as a separate virtual screen.

If I wanted a bigger monitor I would of just bought a bigger monitor, dammit …

Re: The Peculiarly Quiet Decline and Fall of the KVM

#65
post #53

Earlier quoted context omitted.

I've never really understood the desire to use the button on the display to turn off monitors - does allowing the monitors to be switched off by the OS not solve basically the same problem ?

I leave my PC running 24/7 pretty much, so at night I want the monitors turned off so it doesn't illuminate the whole living room (which I can see from the bedroom - it is a small apartment). I used to turn them off with the button on the monitor (when all my monitors were DVI), so if the mouse was moved by accident during the night it wouldn't wake the monitors up. Right now I have to let it go to sleep normally, an…

$ xset dpms force off

and flip the mouse or just run it on loop every minute or so. works for me.

Re: The Peculiarly Quiet Decline and Fall of the KVM

#66
post #3

PSA: It's about this "KVM": https://en.wikipedia.org/wiki/KVM_switch Not this: https://en.wikipedia.org/wiki/Kernel-based_Virtual_Machine

I could never understand why the makers of KVM the virtual machine thing didn't realize they had overloaded an acronym. It isn't as if they weren't likely to have come across KVMs in their work. Were they non-native-English speakers perhaps?

Re: The Peculiarly Quiet Decline and Fall of the KVM

#67
post #52
post #25

KVM switches used to be a huge and super important (and expensive) thing in rack server farms back when every rack or every few racks had a pull-out tray with a keyboard and a monitor. Technology moved on. First the tray and monitor disappeared with KVM-over-IP, which saved many trips to the server room. Then the KVM switches themselves disappeared, as manufacturers integrated out-of-band remote access into the serve…

> Cut a HDMI cable in half and splay it out, then try switching that to another display. See what happens. If you took an ancient (but still available to buy) 25-pin 'parallel port' 4-port switch box with a rotary dial: https://photography-909a.kxcdn.com/product-images/03292/600/... And wired up the HDMI of two machines to output ports 1 & 3[1]. Then wired up the HDMI to the display to the input port (so effectively…

Not likely. If the cables are short you might get away with it but not likely.

The problem you will have is that the signals require high bandwidth and the cables are carefully designed to have low crosstalk, high immunity to noise (both via twisted pairs) and a 100 ohm characteristic (dynamic) impedance (how the cables are constructed, insulation thicknesses, how they are twisted).

DB-25 switches work for simple single ended low frequency signals. The physical switch will wreck havoc with the interpair skew, far-end crosstalk, attenuation and differential impedance.

HDMI 1.3 defines two cable categories: Category 1-certified cables, which have been tested at 74.5 MHz (which would include resolutions such as 720p60 and 1080i60), and Category 2-certified cables, which have been tested at 340 MHz (which would include resolutions such as 1080p60 and 2160p30). Category 1 HDMI cables are marketed as "Standard" and Category 2 HDMI cables as "High Speed". This labeling guideline for HDMI cables went into effect on October 17, 2008. Category 1 and 2 cables can either meet the required parameter specifications for interpair skew, far-end crosstalk, attenuation and differential impedance, or they can meet the required nonequalized/equalized eye diagram requirements. [1]

[1] https://en.wikipedia.org/wiki/HDMI#Cables

Re: The Peculiarly Quiet Decline and Fall of the KVM

#68
post #6

I'd guess the comment about HDCP is onto something. To build a KVM switch that works with modern displays without weird errors, it probably has to be an active HDMI/HDCP endpoint on its own - which means a vendor would either need to get its own sets of keys and do additional work to enforce all DRM restrictions - or they'd have to use leaked keys and prepare to get sued in an instant. Even without HDCP, I remember a…

HDCP seems to work absolutely fine with the plethora of HDMI switches available on the market right now, so that can't be the issue.

Re: The Peculiarly Quiet Decline and Fall of the KVM

#69
I still would like a personal one, I get to work from home frequently, and have a personal desktop, personal laptop and work laptop that'd be great to switch between without having to keep changing plugs (as it is, I velcro the HDMI, mouse, keyboard and speaker jack together to keep it easy to handle).

Re: The Peculiarly Quiet Decline and Fall of the KVM

#70

Earlier quoted context omitted.

The easiest solution is to just buy an HDMI switch(there's loads of them, even ones which work with 4K signal, and they don't disrupt DHCP) and a USB switch. Total solution should fit in about 40-50 dollars.

Are there any that don't suck bogwater? We've tried a handful for our conference rooms, and they are all universally flaky, with signal dropping randomly all the time.

I found that HDMI switches lose signal because the output device doesn't provide enough power for the switch to leach off. I've had a few of Aukey switches: https://www.amazon.co.uk/Switcher-Output-Splitter-Control-Bl...

And once you plug in a dedicated 5V power supply they are rock solid.

Post reply on HN