Strange issue with IGEL UD2 / IGEL OS 11.02.150 upon reboot monitor goes to “No Signal” and does not reboot


Having a strange issue with my UD2-LX50 devices (11.02.150) where they are set to be powered on all the time and connected to a touchscreen monitor to DisplayPort. The issue comes when we have to reboot them, the DisplayPort monitor goes to “No Signal” and doesn’t reboot the IGEL. The local tech has to actually unplug the DisplayPort cable, reboot the thin client, and while that is rebooting, plug the DisplayPort cable back in to fix it.

Learn more, read the entire thread inside the IGEL Community o Slack

What is the model of active DisplayPort cable you are using?

blog.tripplite.com/whats-the-difference-between-passive-and-active-displayport-adapters

Should be looking for

Requirements:

• DisplayPort 1.2 compliant

• active

• supporting up to 4k (60Hz preferred)


Could you please consider to test the latest 11.05.133? We fixed a lot of issues on Display port handling AND, please check if that helps:

kb.igel.com/igelos-11.05/en/solving-hotplugging-issues-with-display-port-monitors-42010395.html kb.igel.com/igelos-11.05/en/solving-hotplugging-issues-with-display-port-monitors-42010395.html


Good question. I know he doesn’t use any sort of adapter there. I think it’s just a straight DisplayPort cable to be honest.

I’ve tried those Hot Plugging changes and created a support ticket for IGEL too (thought I included that in my message).


Ok, great! Is Update an option?


Yeah, it should be. Talking with my team now. I read that I need to upgrade UMS first (6.03.110), and also need to switch from local DB to SQL DB. Whoever set this one up didn’t do it properly. 😕


Oh, that’s a pitty… But for the pure update process, it shouldn’t matter :hugging_face:


As far as the hotplugging options… This was what I set:

Do those look like they are conflicting though?

I tried just the options that the article suggested, but that didn’t work for me 😞

Then I switched to what I linked there just now.


Are your cables active or passive?

If you are using a DisplayPort to HDMI, DisplayPort to DVI, DisplayPort to VGA or HDMI to VGA cable and are having issues we recommend using an active video adapter in conjunction with a video cable as illustrated below:

DisplayPort output > DisplayPort to HDMI active adapter > HDMI to HDMI cable > Monitor input

DisplayPort output > DisplayPort to DVI active adapter > DVI to DVI cable > Monitor input

DisplayPort output > DisplayPort to VGA active adapter > VGA to VGA cable > Monitor input

HDMI output > HDMI to VGA active adapter > VGA to VGA cable > Monitor input

What is the difference between active and passive?

Active cables and adapters contain have their own built in chip which converts the video signal from say DisplayPort to HDMI, they also convert the digital DisplayPort or HDMI signal to the analogue VGA signal

Passive cables and adapters do not have such a conversion chip built in. Instead they rely on the source to do the conversion. Unless the source has the ability to output analogue over DisplayPort or HDMI then an active adapter is required for VGA output.


It shouldn’t conflict, but let me ask another thing: is your device still online in UMS when the Display goes black, after sending reboot?


No, they are powered off still.


Which Display port “port” did you used on the backplate? The upper one or the other, down?


I will look into that for him. So if he’s just using a straight DisplayPort cable, he will need to get one of those adapters to enable Active Cables instead. I believe this is how one of the other sites is configured that doesn’t have any problem.

He told me he tried both of them and same issues. Which one should it be?


Why upper DP? I thought the bottom one is DP1 (closest to power supply connector) on the UD2?

Did you say it’s just a passive DP to DP cable connecting to monitor DP port?

if it’s just passive DP cable connecting to DP monitor, why the recommendation for active adapter?

Just took another look to make sure I wasn’t going crazy. On the UD2-LX50, the bottom port (closer to power supply) is indeed “DP1” (shown by IGEL Display Switch just as DisplayPort, and reported by xrandr as DP-1). The top port (closer to ethernet connector) is “DP2” (shown by IGEL Display Switch just as DisplayPort(II), and reported by xrandr as DP-2).

I wonder if the problem is related to power save settings / DPMS settings, and if your monitor doesn’t properly handle this signaling. If you have it on, did try turning off “Handle Display Power Management”. And if you have it off, did you try turning it on?

I found this to be a great resource when testing monitor DPMS capabilities:

shallowsky.com/linux/x-screen-blanking.html

sleep 1; xset dpms force off


So this is the cable that he is using — no adapter or anything, just a straight cable:


Right @member !! My mistake!! Thank you gor correcting, will delete the misleading post👍🙏


@member Standard DP cables should be fine from my experience. Did you try a cable swap yet? or a monitor swap test?

What is the monitor behaviour when powering the IGEL on? Does it show anything happening?

Can you try turning the IGEL off, and checking the sequence? It should be:

1. With IGEL off – does monitor just show “No signal”/possibly followed by screen off?

2. “IGEL Workspace” only (low-res)

3. “IGEL Workspace” with Version Number, and pulsing logo

4. Black screen

5. Desktop loads

Does the monitor do anything in those situations?


Did you try a cable swap yet? or a monitor swap test? or a monitor swap test?

This happens on all of the devices with the same monitors and cables. The same device and monitors seem to work at another location that is using HDMI -> DisplayPort adapters.

What is the monitor behaviour when powering the IGEL on? Does it show anything happening?

No signal is displayed.

It should be:

1. With IGEL off – does monitor just show “No signal”/possibly followed by screen off?

2. “IGEL Workspace” only (low-res)

3. “IGEL Workspace” with Version Number, and pulsing logo

4. Black screen

5. Desktop loads

Does the monitor do anything in those situations?

It does not. When you power the IGEL with the monitor plugged in, it just shows “No Signal.” If you unplug it, then power cycle the IGEL, and then plug it in after the IGEL is booting it, it then seems to work.

Let me rephrase that, it’s the same model of monitors and IGEL thin clients from the one location that works compared to here. The major difference being that one is using HDMI -> DisplayPort Adapter -> Monitor compared to a Straight Cable here, which is not working.


And, if not too late and disabled in a profile, press

CTRL ALT F10

Does it show something, stays black? I know it sounds weird but could you on your displays OSD (Menu) if there is something like Powersave mode or a different Bios then another Display?


The display is a ViewSonic TD1655

www.viewsonicglobal.com/public/products_download/user_guide/Display/TD1655/TD1655_UG_ENG.pdf?pass

I’m looking into the options now from the manual. I’m not located there to test it

wait, maybe this is a different monitor… let me check with the tech


Clarification: With the monitor plugged in, and the IGEL off. Will pressing the IGEL power-button cause the IGEL power-led to turn on, and then “beep”, and seem as if it’s powering on? Or does the IGEL led stay off?

Asking because of this: www.reddit.com/r/buildapc/comments/56e3vb/new_build_wont_boot_with_displayport_connected/


I sent him that. Waiting to see if it will work. If this does, I owe you a beer!

_With the monitor plugged in, and the IGEL off. Will pressing the IGEL power-button cause the IGEL power-led to turn on:_

_YES_

_and then “beep”_

_YES_

_and seem as if it’s powering on;_

_Yes it does seem as if it is ON only thing that does not come on is the monitor_

_Or does the IGEL led stay off;_

_NO it is turns ON_

Those were his responses


Too bad…I was hopeful. 🙁

1. Can you try different brand of cable?

2. A newer IGEL Firmware version? Anything 11.04 and later is a one way trip (you can downgrade to 11.02 but only via USB OSC). But 11.04/11.05 are based on different kernel+base so the behaviour might change.

To me it seems unrelated to any TC settings and more to do with how the base OS sets up display mode with that monitor+cable.


He will try out the tape method on Monday. It is possible it might work for him.

I was going to jump to the latest IGEL firmware, but before I do, I think I need to do a UMS upgrade. The problem with that is I heard it’s a little risky because it’s the DB is not in SQL.

if we can get by with just taping the pin, that would be way better! And I agree, I do not think it’s think client related but just something with the cheap cables he’s using, lol.


Setup a VM of UMS for testing — Here is a link to setting up sandbox for UMS etc.

igelcommunity.slack.com/archives/C015V0F5KFY/p1620077644171800


To upgrade to 11.04/11.05, I think it’s recommended that you upgrade your UMS so that you get all features/settings exposed in the UMS configuration, rather than only in the UMS “registry”, but it’s not a hard requirement. I think that’s what @member meant when he said:

igelcommunity.slack.com/archives/CBJDENFFY/p1620331752294200?thread_ts=1620329048.289200&cid=CBJDENFFY

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