Changes/EnableConsistentDeviceNamingCloud

Enable Consistent Device Naming in Cloud Images

This is a proposed Change for Fedora Linux.
This document represents a proposed Change. As part of the Changes process, proposals are publicly announced in order to receive community feedback. This proposal will only be implemented if approved by the Fedora Engineering Steering Committee.

Summary

This proposal aims to remove the net.ifnames=0 kernel command line entry from the Fedora cloud kickstarts so that consistent device naming is enabled for cloud instances.

Owner

• Name: Major Hayden
• Email: major@redhat.com

Current status

• Targeted release: Fedora Linux 41
• Last updated: 2024-03-18
• [<will be assigned by the Wrangler> devel thread]
• FESCo issue: <will be assigned by the Wrangler>
• Tracker bug: <will be assigned by the Wrangler>
• Release notes tracker: <will be assigned by the Wrangler>

Detailed Description

Fedora cloud images currently set net.ifnames=0 on the kernel command line during the kickstart process. This disables consistent device naming and ensures that ethernet devices retain the old-style names of eth0, eth1, eth2, and so on.

Removing the net.ifnames=0 configuration allows Fedora cloud instances to use consistent device names for network devices. This brings Cloud images in line with Fedora Server, Workstation, and CoreOS.

Feedback

One of the proposed alternatives is to leave net.ifnames=0 in the kernel command line to remain consistent between releases. Although RHEL allows for net.ifnames=0 for KVM instances, it is recommended not to use it with OpenStack or RHV environments. Fedora Cloud images are used for multiple types of clouds, including public clouds and private clouds.

This approach is less disruptive, but it pushes off the consistent device naming change until a later date and causes cloud images to operate differently than other Fedora deployments.

Benefit to Fedora

The main benefit comes from bringing cloud instances inline with other deployment types in how they name network devices. It also helps with cloud providers that offer up different types of network interfaces to an instance. For example, an emulated network device would present itself differently than one offered via SRIOV and it would allow an instance administrator to easily tell which network interface corresponds to each network device.

Scope

• Proposal owners:

• Other developers:

• Release engineering: #Releng issue number

• Policies and guidelines: N/A (not needed for this Change)

• Trademark approval: N/A (not needed for this Change)

• Alignment with Community Initiatives:

User Experience

Upgrades: Users who are upgrading to the next Fedora release will not notice a change in their instances since the net.ifnames=0 change is only applied during the kickstart process. Their instances will continue using the old network names.

New deployments: If a user has older Fedora deployments and they deploy a new Fedora release with this change applied, their network devices will use consistent network names instead of the old eth0 and eth1 style names. Although this won't impact software like cloud-init, it will impact users who have deployment scripts (Terraform or Ansible, for example) that need to set network configuration based on the network adapter's name. They will need to adjust the name of the network device in their deployment scripts.

Contingency Plan

• Contingency mechanism: (What to do? Who will do it?) N/A (not a System Wide Change)
• Contingency deadline: N/A (not a System Wide Change)
• Blocks release? N/A (not a System Wide Change), Yes/No

Documentation

N/A (not a System Wide Change)