starting web access without a monitor

[Uncle]

Hello
I have an Rpi 3b with a fresh install of 4.12.2 and it boots great with a monitor plugged in via HDMI but it will not start the web access if a monitor is not plugged in. I was hoping to put the Pi under some furniture and access it via the web access. I'm assuming I need to change a setting somewhere but I havent been able to discern where. When I SSH in and sudo service qlcplus status I get:

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qlcplus.service - LSB: Q Light Controller Plus
   Loaded: loaded (/etc/init.d/qlcplus; generated)
   Active: active (exited) since Sun 2019-09-15 09:49:31 PDT; 1min 25s ago
     Docs: man:systemd-sysv-generator(8)
  Process: 446 ExecStart=/etc/init.d/qlcplus start (code=exited, status=0/SUCCESS)

Sep 15 09:49:30 raspberrypi systemd[1]: Starting LSB: Q Light Controller Plus...
Sep 15 09:49:31 raspberrypi qlcplus[446]: Starting Q Light Controller Plus: qlcplusSep 15 09:49:31 raspberrypi systemd[1]: Started LSB: Q Light Controller Plus.

When I do have a monitor connected I have web access with no issues.
Any help would be appreciated.
Thanks

[mcallegari]

As far as I know, monitor plug has nothing to do with the network nor web access.
Do you actually ping the RPi IP address without a monitor?

[Uncle]

Yes I can ssh in with no monitor plugged in but can't access via webaccess.

[mcallegari]

Weird...
Can you check via SSH if QLC+ is actually running without a monitor?

[Uncle]

Sorry how would I do that other than:
Sudo service qlcplus status
Which shows active (exited)?
I'm still learning linux.

[mcallegari]

With the 'ps' command you can see the running processes. Just type

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ps -ef | grep qlcplus

and copy the output here please

[Uncle]

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pi@raspberrypi:~ $ ps -ef | grep qlcplus
pi        3325  3307  0 10:05 pts/0    00:00:00 grep --color=auto qlcplus

[mcallegari]

Then qlcplus crashes if no monitor is connected. This is no good.
I'll investigate the cause of it

[mcallegari]

Hi, yesterday I checked this.
Unfortunately no good news.
The issue is confirmed and apparently it's not in QLC+ so I can't fix it. It seems there's something wrong between the Qt libraries and the RPi graphics driver (VC4)
I really hope they will fix this upstream...and soon, because this is quite a common usage case (headless) and it's not acceptable if it doesn't work.

I'm gonna see if I can report this issue to the Raspbian team.
I'm afraid meanwhile you need to plug something on the HDMI, even if you don't use it

[Uncle]

Thanks for the reply

[GGGss]

5$ HDMI dummy plug?

[BassManTL]

sadness...

[mcallegari]

I've got some feedback from a Raspberry guy.
It seems there's a parameter in config.txt that pretends something is plugged on HDMI.
Can you please try to add this to config.txt and reboot?

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hdmi_force_hotplug=1

It's obviously a workaround, but it might do the job.
Also, it seems this issue might affect RPi 4 users only. I'll check both when I can.

[alanle]

Thanks for the WA, it works perfectly!

[alanle]

Looking for another thing, i found this post related to HDMI. At the end, one user post two scripts that could be helpfull regarding HDMI

https://www.raspberrypi.org/forums/view ... hp?t=12332

[ralbrightii]

I've got some feedback from a Raspberry guy.
It seems there's a parameter in config.txt that pretends something is plugged on HDMI.
Can you please try to add this to config.txt and reboot?

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hdmi_force_hotplug=1

It's obviously a workaround, but it might do the job.
Also, it seems this issue might affect RPi 4 users only. I'll check both when I can.

I can confirm the same issue exists with RPi 3. I am experiencing the same issue. I will load the code you indicated, and report back soon.

[ralbrightii]

Fixed it for me on a Rpi 3