Delete old-non-image-installation

Hello. Under which circumstances can I securely delete an “old-image-installation”?
The reason I’m asking is because I couldn’t figure out yet when this image is generated. I was thinking it was when one adds a new system image and selects “the save configuration” option, but some time ago I added a 1.1.8 image to 1.1.7 running system, without saving the configuration and the Show system image only shows:
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I think when I delete an “old-image-installation”, any newer image won’t boot. But if a system has an old version with it’s version as its name, I can securely delete it. Am I right?
Thanks and regards.

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David

Those images are generated when you upgrade.

In modern versions when you would do add system image http://path/to/new/vyos.iso, this would prompt you to set a name.

This makes it so on boot, you have a list of images you can boot into. For example if you upgrade and there’s a problem with the new version, you can reboot into the original pre-upgrade installation easily.

So the answer is, you can delete them when you are sure you don’t need them anymore.

Thanks for the reply. The thing is I’ve had some bad experiences (lost all configuration) on some machines which displayed the “old-non-image-installation” that I removed. Lately there hasn’t been any problem. today, for example, I’ve upgraded 1.1.8 to 1.2.2 and removed version 1.1.8, and everything works fine. Please note that I’ve been upgrading selecting the option to keep the existing configuration. But there was a case where I did this and removed “old-non-image-installation”, and completely lost the config.
Why?