TLDR: Due to a bug, all current FCOS machines are using legacy network
interface naming (e.g. `eth0`). Fixing and changing the default naming
scheme will be targeted at freshly provisioned instances *ONLY*.
Existing instances will be able to switch to the new scheme via manual
Due to an oversight, network interfaces (NICs) on Fedora CoreOS are
currently named using the kernel's default scheme (e.g. `eth0`).
Depending on the order that devices are discovered, these names can
change from boot to boot.
Unfortunately we did not realize this until recently, as described in
#484. This means that currently all FCOS nodes on all streams (thus
including `stable`) are not using predictable interface names as
used in other Fedora Editions and Linux distributions.
Starting with the next release cycle we plan to fix this bug, thus
changing the default behavior for new Fedora CoreOS releases.
As this is a quite invasive behavioral change, it will only affect
newly-provisioned machines. NIC names on existing systems will not
change, as upgrades there will automatically pin the current behavior
via the kernel command line.
The ticket above has further details on the plan of action, but in
short we are going to:
* (in the upcoming release cycle) pin existing nodes into their
current naming scheme
* (in the release cycle after that) switch to persistent naming scheme
for new nodes
If everything goes as planned, the end result is that:
* freshly provisioned instances will use the persistent naming scheme
* existing instances will stick to their existing naming scheme
* in those cases where it is safe to change existing behavior, manual
intervention can be applied to opt-in into the new default behavior
If you deploy Fedora CoreOS using an Ignition config that references
NICs by name, you'll need to update your config to reflect the new
naming. Also, if you have a mixed fleet of older and newer Fedora
CoreOS installs, note that NIC names may not be consistent across
machines (unless manually switched).
We will keep posting progress and updates to the bug tracker, please
keep watching #484 for details.