Transactional Updates with btrfs
Channel: FOSDEM
Date: 10/03/2018

by Thorsten Kukuk

At: FOSDEM 2017

While small updates normally don't disturb the services running on yoursystem, bigger or intrusive updates can break your running services orDesktop. There are different ways of doing transactional updates like newpackage formats or different partitions. This talk will show how to use thefeatures of btrfs for this with traditional package managers.

Applying small updates is normally no problem in a running system. But whatabout if there is a new major release of your favorite Desktop? Or a majorversion update of your used Linux distribution? Today’s concepts are most ofthe time to apply the patches in the running system and risk that a runningservice or Desktop breaks, or apply them all by booting an installation mediaand wait for quite some time until you can access your machine again. Asolution for this are transactional updates.

Transactional updates are atomic, means either they applied successful, or ifan error occurred, you have the same state as before. And if an update doesnot work, there is an easy way to go back to the last working state.

There are different solutions for this, some require new package formats,other require a second partition and you can switch during the next reboot tothe other partition. I want to present a third solution: using a standardpackage manager and leverage btrfs for this. With snapshots and rollback onbtrfs, there is already everything available what you need. This talk willgive a short introduction into snapshots and rollback with btrfs and show howto combine and use this technologies to your advantage.


Room: K.4.601
Scheduled start: 2017-02-04 14:30:00