Failover

[mariofrombelgium]

Hi All,

had my second show last Saturday. I literally saw QLCplus 4.14.0 go down on my Windows 10 pc Four times.
I need to investigate why ...it really can't happen again.
I have a new show in three weeks. I hope I can find what caused the blackouts and solve the issues.

Next to me trying to replicate the problem and going through the WIndows LOG files I would like to ask the community the following questions :

1° Do you see a difference in stability between the WIN and the LINUX versions? I work have both and have the feeling the LINUX-version is more stable. (wanted to use that version but for other reasons needed to go for WINDOWS-version.

2° are there ways to setup a system in failover? I'm interested to learn about any method possible.

3° is there a way to have a DMX- backup-system that kicks in whenever the main QLCplus connection drops. That would keep the lights up to a preset DMX-value-set just until I have the QLCplus back on.
The crowd will probably "feel" something strange about the lightning but at least it wont be a complete blackout.

4° the show last saterday was done with a ENTECC DMX PRO MKII directly via USB connected to the pc. In three weeks I'm planning to go back to a setup that I used a couple of months ago where I connected the ENTECC to RaspPi4 setup as OLA server. That worked perfectly throughout the show.
What would be the recommendation from the community? In other words, would I increase stability by separating DMX-dongle from the QLCplus controller pc? Or not?

Please don't keep yourselves in! Any, literally any, recommendation is much appreciated.

As soon as I succeed in replicating the issues of last Saturday I will come back with (probably more questions) the results.

Grtzz,
Mario

[Freasy]

Hi,
are you using any RGB-Matrix functions? There are some issues with it in the current official version which as far as I know are fixed already but not released yet.
I used version 4.14.0 for two shows lasting each about 5 hours and had no crash, QLC+ ran very stable. I use Linux Ubuntu Studio 24.04 LTS on an Intel NUC.

Edited to make it clearer:
In older versions (before 4.13):
I actually only had one or two times a freeze of the program during the show in the past, but that always was related to some changes I did on the fly (editing the virtual console during the show), all the crashes I had (which weren't that much) happened during programming.
You also might want to check the power settings of your PC, if Windows decides to shut down the DMX interface because it hasn't been used (or at least it thought that it hasn't been used).
Also as far as I'm aware there might be some issues with interfaces on Windows in 4.14.0 which as far as I know are also fixed already in the next version.

To 1: I don't know if there is a significant difference between Windows and Linux, I use Linux since it's a more stable system overall and only used Windows for programming on a "big PC". I have a colleague who uses Windows, but his DMX-interface is some cheap one, so can't really compare that.

Regarding 2 or 3: I don't know if there are DMX interfaces which have a "last state" function (if no signal, keep the last values). Depending on which fixtures you use, there might be a function in the fixture itself where you can set what should happen if DMX signal is lost.
QLC+ itself has no "failover". I'm carrying a simple DMX fader controller as a backup but never had to use it.

To 4: I always connected the interface (I'm using an ENTTEC DMX USB Pro bought in 2015) directly to the system where QLC+ is running. Can't remember having any issues with it, except one time where the USB-cable was broken. Switched that out and it worked again.

But back to your crashes:
What where you doing exactly when the crash happened?
Was it crashing after one specific function? Was it completely random?
If you can't say what you did before it crashed it is very hard to track down what caused it.

[Rhinesel]

In reply to stability, I have run many shows on Windows without any crashes or issues. These were community theater style shows running all functions in a chaser.

[mariofrombelgium]

Hello,

are you using any RGB-Matrix functions? There are some issues with it in the current official version which as far as I know are fixed already but not released yet.

The answer is yes. Even more, at the time of the crashes QLC was only running one RGBmatrix and one scene.
I wasn't touching anything because I had a crash at the beginnng of the show when I was using a flashbutton....probably somewhat too intense. Anyway, after that I decided to just start my RGBmatrixes and scenes and than leave the system until I started an "end-of-song-chase" and go to the next song. Each song had its RGB-matrix and scene.
Literally nothing else was running with no interference from myself.

I'm not going to focus on the crash wile using the flashbutton. I can obtain the same, probably even better, functionality without the flashbutton.

Crashing during the RGB-matrxes is dramatic. I will test them thoroughly and report back.


However, since I have a new show in three weeks, what do you suggest. Go back to an older version of QLC ?


Regards,
Mario

[GGGss]

Mario,
Go back 2 versions: 4.12.7 for stability reasons (and RGB matrix issues). The thing is that Massimo had to switch to a more modern version of QT, and this has induced problems coming from outside the QLC+ environment. So he had to debug a bug which wasn't there and came in since the buggy component bugged the QLC+ engine. Go figure...

In general:
* With all the 'intelligent' interfaces I have worked with, it's dead stable for weeks if you like. Attention to pay is at the power settings of the USB ports. When in doubt, check the power consumption of your interface. (An Enttec pro MKII needs 600mA, where a default (older) USB port only delivers 500mA as per spec. In this case, you'd need a powered hub.)
* I almost always have my fixtures in the 'hold values when no DMX is present' mode. If I feel something is fishy, I unplug the DMX cable, and your stage will stay lit.
* A backup system is possible by using a DMX merger, but you need to create a strategy for how the merger will know which input is now valid. (Unplugging the DMX cable from the faulty sender). You cannot get a backup solution 'in session', where the backup table will flawlessly surpass the defective table. This is for the big guys (and ditto investments)...
* 4: You add complexity to the system, hence more places where hiccups can happen. Since your crashes point back to RGB matrixes, IMHO there is no need to alter the setup.

[mariofrombelgium]

Thanks All,

I reverted to 4.12.7 as suggested by Fredje.
I hope to be able to have a good trial run to see if problems arise and leave the 4.14. version (for now) aside!

Thx for the support, very much appreciated!