Dry runs and DNS

[thoresson]

Hi!

I'm in the process of migrating from one VPS to another, and while waiting for the backup of my old installation finish I read through the docs once more and realized that there is one thing I don't understand: What does "Dry run" do?

I get that this is a feature that let me test my Cloudron on the new server before pointing the DNS to it. What I wonder is more like how Cloudron can make those changes in the first place?

I'm using the Wildcard configuration, and in the settings at my registrar point the A records to the IP address of my current VPS. How could Cloudron change those settings if I don't check the Dry run option?

What am I missing?

[nebulon]

In such non automated DNS provider cases, Cloudron cannot change the DNS records, but it will expect you to have those still setup. During a dry run it skips those checks internally.

[thoresson]

Ah, that make sense. So then I better select Dry run to not have any internal checks fail, change DNS manually, and after that are good to go? The Sync DNS wont work either for Wildcard DNS?

[nebulon]

Yes you should be fine then. And also yes, Cloudron cannot magically update DNS records if manual or wildcard DNS backends are used.

[msbt]

Sorry for semi-hijacking this topic, but since it's somewhat connected, I think it's okay

I'm also about to migrate a VPS with a bigger setup. It uses a number of custom apps and the Docker registry is also part of the Cloudron apps. The migration can only work if I do a dry-run, right? If the Docker registry isn't up during the restore process, the apps can't pull from the live-registry, or am I overthinking this and it will work because it is either still online on the old server or will be on the new one? Are there "priority apps" during the restoration which would make it easier? I think I saw multiple apps being restore at once, so that wouldn't work.

[nebulon]

Not sure I fully understand the setup, but if your Cloudron has apps installed where the image is pulled from a registry app running on the same Cloudron, this does not sound like a great idea in the first place, if you need to restore from scratch.

For you server migration, it does sound then like it only will work with dry-run.

[msbt]

Thanks for clarifying. Yeah I realized that a while ago, planning to do it differently, maybe even before the migration!