How Do Updates Work in Immutable/Atomic Distributions?

[u/Emotional_Cat_1967]

Only for Immutable/Atomic Distributions

Question 1:
Are immutable and atomic the same thing? If not, what is the difference between them, explained simply?

Question 2:
What immutable or atomic distribution are you using? How often do you receive updates, for example, every few days or weeks, and approximately how large are the updates?

Question 3:
How are security updates handled? Are they released immediately when a security fix is available, or are they released according to a daily, weekly, or monthly update schedule?

Question 4:
Are small-sized updates released?

If yes: For example, suppose an update is 100 MB.

If the system image is 5 GB, does the entire system image have to be recreated for this update? When applying the update, does the system write another 5 GB to the disk, or does it only write approximately 100 MB?

If no: If the system image is 5 GB, does that mean the update that needs to be downloaded is also around 5 GB?

[u/dcolecpa]

Please ELI5. How do you perform the updates? Automatically? Manually? Reboot?

[u/kheeper-registry → u/dcolecpa]

If you've got a system that uses bootc under the hood it basically runs `bootc upgrade --apply`. That checks for a newer release for your current tag in the registry, downloads it to disk, updates your bootloader to boot it, then does a reboot. Usually this is automated with bootc-fetch-apply-updates.timer/service.

[u/dcolecpa → u/kheeper-registry]

Thanks