Thanks everyone for the helpful replies!

On Wed, Sep 25, 2019 at 2:07 PM Benjamin Gilbert <> wrote:
On Tue, Sep 24, 2019 at 1:52 PM John Osborne <> wrote:
Q: It looks like I can turn on automatic updates on FCOS by editing /etc/rpm-ostreed.conf. Will that make my machine auto-reboot? When?

Automatic updates are handled by Zincati, which receives information about new updates and then drives rpm-ostree to apply them.  They're enabled by default, via the Zincati service and not rpm-ostreed.conf.  By default, your machine will automatically reboot after applying an update, though you can configure Zincati to e.g. request permission from an external system first.
Are the updates in an OCI image (oscontainer)? Where is the image unpacked? How does ignition know which image to use when it starts the machine?

Updates are pulled from an ostree repo.  Fedora CoreOS ships fresh boot images for every release, so on the first boot we just start the OS version shipped in the disk image without applying any updates first.  After an update, rpm-ostree configures the bootloader to boot into the new OS version.

--Benjamin Gilbert


John Osborne

CHIEF openshift architect, RHCE

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