Temporarily boot current Silverblue image without /etc modifications

Ask Fedora
1

I’m experiencing a weird issue with Silverblue 41 I didn’t have when I first installed, so I wanna test if /etc modifications could have anything to do with it.

Is there a way to temporarily boot the current image but without any /etc modifications?

2

I guess

  1. Get a USB-to-SATA / NVME adapter and a second SSD at least the same size of your current one.
  2. Use clonezilla and clone your current system to the different drive
  3. Boot into that drive
  4. Create a read-write subvolume mounted at /etcold (or is it /var/etcold?)
  5. Copy /etc to /etcold
  6. Use the experimental reset command which basically does an rsync from /usr/etc (which stores the current defaults) to /etc
  7. Reboot
  8. If it goes well, stay, if not you can still copy the contents of /etcold to /etc and it should work again

This is really experimental. In theory it is not thaat bad and /etc is normally not changed by the user. Only some things should be, and I think we got them all in the custom rsync command.

But still, be cautios and have a backup.

3

You may want to read through Factory reset with OSTree · Issue #1793 · ostreedev/ostree · GitHub

Is there any reason you can’t manually revert the changes AFAIK etc is mutable.

4

Thanks for that information. I assumed that since Silverblue overlays /etc modifications over the base image it had a straightforward way to temporarily boot the base image without modifications, but it looks like these are the available options.

Is there any reason you can’t manually revert the changes AFAIK etc is mutable.

I can make modifications to /etc but quite frankly I don’t know where to look. Perhaps the issue isn’t related to any /etc modifications whatsoever. So I was hoping that if I booted the image without the overlay I’d be able to see if that’s the right angle to investigate.

5

Look at Updates, Upgrades & Rollbacks :: Fedora Docs and Tips and Tricks :: Fedora Docs.

6

Note that this will deploy the exact version as requested and will not include overlayed packages and other changes.

Excellent, that’s just what I need. Thanks!

1 Like
7

Note that this is not quite correct, or not correct anymore. I have already filed an issue against that part of the HowTo.

8

That’s unfortunate, thanks for flagging this. I might still be able to use the tip Hristo shared to figure out which files got changed and identify a likely culprit.

1 Like