OSC backup bug

[Bassindaniel]

Hi.

I’m encountering an issue with Resolume Arena while running a hot backup setup.

I have two machines connected via a network cable, using OSC communication for redundancy. When the primary machine crashes and I restart it, the composition resolution on the backup machine automatically reverts to 1080p, instead of maintaining the original resolution of the composition.

OSC is only outputting some command such as next column and dock scrolling...

This unexpected behavior disrupts the continuity and requires manual adjustment each time.

Could you please advise

[Zoltán]

Switch off OSC input on the slave while restarting the master. Then change the OSC direction, your backup is now the master machine.

[Bassindaniel]

Thanks for the suggestion, but this workaround doesn’t make sense in a real-world live show workflow.

In the middle of a major event, when a crash occurs, there’s no time to manually disable OSC input, restart, and then reconfigure the network direction. The whole point of a hot backup setup is to ensure seamless continuity — not to require manual interventions during a critical moment.

The issue here is that the backup machine receives some kind of default resolution reset (1080p), which seems to be triggered when the master reconnects. That shouldn’t happen. The backup should retain the original composition resolution regardless of OSC communication state.

This looks like a bug and I hope it can be addressed properly in a future update.

[Zoltán]

OSC master-slave is not an official feature. Simply sending unfiltered OSC from a Resolume instance to another one will give issues, explained a few times on the forum. So, that said,

You don't need to restart the slave, just disable it's OSC input. Total 3 mouse clicks.
4 if you enable the output you have set up previously.

The issue here is that the backup machine receives some kind of default resolution reset

The backup is your main machine now.
You start up a different machine which is in a different state which will send out OSC.
Do you want that state to be taken over on the live machine?
No? disable OSC input.

A better setup would be triggering both machines from an external source, then it won't matter which one is live at a time.

[Bassindaniel]

I don’t need or want OSC to be an official backup feature.

All I’m asking is that you find the line in the code that mistakenly resets the composition resolution on the receiving machine — and remove it.

It used to work just fine, and there’s no reason it shouldn’t work again.

That’s it. No workaround, No settings tweaking in a middle of a show. Just fix the bug Please.

[Christoph]

Do your 2 machines have similar specs, especially the GPU?

There is a fix prepared for 7.24 that should prevent Resolume from outputting a shitload of OSC messages on startup if you haven't selected "Output All OSC messages".

[Zoltán]

All I’m asking is that you find the line in the code that mistakenly resets the composition resolution on the receiving machine — and remove it.

On Resolume startup, stuff is initialized with with default values. The OSC output you see is correct for that.
The last composition gets loaded after that.

Again, OSC is not designed to run direct backups, You'll have to have a custom OSC preset and/ or an message filter between the machines for it to work as You'd expect it.

[deflost]

so, what is the official hot backup option for resolume? thx.

[Zoltán]

Triggering both machines from a third source, no communication between the Resolume machines.
This can even be done with single broadcast OSC messages, or DMX shortcuts.