Updating and rolling back

One command updates everything, and one undoes an update if something goes wrong.

Update bromigOS

1. Open a terminal with Alt+Shift+Enter.

2. Run:

   bromigos update
   

3. Type your password when sudo asks, and answer the package manager’s questions.

Or open the menu and choose UPDATE › Update bromigOS, or choose Update now in Settings › Updates & recovery. Both open a terminal for you.

To see what an update would do first, without changing anything:

bromigos update --check

What an update does

1. It updates every package on the system, bromigOS’s and Arch Linux’s, and then the packages you installed from the AUR. It takes a snapshot just before and just after, so you can undo all of it.
2. It runs any migrations: small changes to your settings that a new version needs. A migration that has to change one of your files keeps a copy of the old one.
3. It applies your theme again.
4. It restarts the parts of the desktop that still run old code: the background, the panels, the bar, notifications, the volume display, VECTOR and his voice. Apps that ask for it, such as BRODEC, get their background services restarted too. Your apps keep running: an app that can restart itself does so when you aren’t using it, and one that might be busy, such as in a call, shows a notification with a Restart now button instead.

When the update asks you to restart

A new Linux kernel or a new NVIDIA graphics driver only runs after the computer restarts. When an update installs one, its last line says so, and a notification says the same:

The graphics driver was updated: restart the computer to use it. Until then, the animated background stays off.

Until you restart, the update leaves alone what needs the graphics card: the animated background and VECTOR. Started now, they couldn’t use the card, and would run slowly on the processor instead. Whatever is already running keeps running. Everything else restarts as usual. Restart the computer when it suits you.

If the animated background starts anyway before then, it shows a still picture instead, and a notification says the graphics card isn’t available (Troubleshooting).

When an update brings a new release, its last line says so. To read what the release brings, run bromigos whats-new, or see What’s new.

Use bromigos update rather than sudo pacman -Syu. A plain pacman -Syu doesn’t run the migrations or the restarts, and bromigos update --rollback can’t undo it. When it changes bromigOS’s packages, pacman reminds you to run bromigos update.

Packages from the AUR

The AUR is where Arch Linux users share recipes for software that Arch Linux doesn’t carry. bromigOS installs paru to build them. bromigos update updates the packages you installed from it too, after everything else.

Anyone can write an AUR recipe, and nobody checks it. So before paru builds a package, it shows you the recipe, or what changed in it, and asks. Read it, or trust whoever maintains it.

• bromigos update --check lists the AUR updates waiting.
• bromigos update --no-aur leaves the AUR out this time.
• bromigos update --yes builds without showing the recipes. Use it only for AUR packages you trust.
• If one fails to build, the update still finishes. It tells you which package failed, and how to try again.
• Without a terminal and without --yes, the update leaves the AUR out, and says so.
• bromigos aur off turns the AUR off: bromigOS removes the paru it installed, and updates leave AUR packages alone. bromigos aur on turns it back on.

Undo an update

If an update broke something:

bromigos update --rollback

It shows what the last update changed, such as the packages and how many files, and asks before it does anything. Then it puts every system file back as it was before the update. This happens on the running system. Afterwards, run bromigos restart, or restart the computer. If the update included a new kernel, restart the computer.

To undo an older update, give its snapshot number. bromigos update --check lists the updates you can undo, with their numbers.

bromigos update --rollback 151

In Settings › Updates & recovery, Roll back… undoes the last update.

If the computer won’t start

Start it from a snapshot in the boot menu. That gives you the system as it was before the update, until you restart. To keep it, run bromigos update --rollback there. In a snapshot, it doesn’t undo an update. It makes the snapshot you started your system, so the next normal start comes up on it.

The system you rolled back from is kept, in case you need something from it. The rollback prints how to delete it once everything works.

What you need for snapshots

Snapshots need the system disk to use the btrfs file system, with snapper set up. An install from the bromigOS USB stick has both. To check your machine:

bromigos rollback status

It says whether your updates are snapshotted, and what can be undone. If something’s missing, it tells you what to run:

• bromigos rollback setup sets up snapper, and adds the snapshots to the boot menu.
• bromigos rollback allow lets you list the system’s snapshots without sudo, so updates can be recorded. It asks for your password once.

Not on btrfs? Updates still work. There’s just no snapshot to go back to, and bromigos update --check says so.

Channels

A channel is the stream of updates you follow.

To see your channel and change it:

bromigos channel                    # which channel you follow
bromigos update --channel edge      # switch to edge, and update

Moving to an older channel, such as from edge back to stable, puts packages that are newer than that channel’s back to its versions. bromigos update --channel does this for you.

You can also change the channel in Settings › Updates & recovery.

The manual

This manual is published next to bromigOS’s packages. It follows the newest code, so on the stable channel it may describe things that haven’t reached you yet. In Settings, F1 opens it on the page you’re looking at.