Skip to content

Dummy interfaces #7678

@dann1

Description

@dann1

Description
Add the ability to provide virtual network interfaces without a backend. The idea is to mimic the esxi null interfaces with a generic ethernet connection backed by downed tap device.

Example RAW template

RAW=[
  DATA="<devices>
  <interface type='ethernet'>
    <target dev='dummytap0' managed='no'/>
    <model type='virtio'/>
  </interface>
</devices>",
  TYPE="kvm",
  VALIDATE="YES" ]
SCHED_REQUIREMENTS="

Use case
Some Guest OS might have workloads that validate nic existence.

Interface Changes

  • New network interface type
    • this dummy/null interface type does not require a backing virtual network
  • The dummy driver should be extended to handle this case
    • no bridges are created, instead, each dummy/null interface will be backed by a tap device
      • maybe BRIDGE_TYPE=null or something similar.
    • these tap devices must always be down to avoid any possible traffic

Additional Context
Each nic requires a tap device. libvirt allows managing the device automatically, even the name, with the use of

  • dev='mytap1' # define name or automatically generated by libvirt as vnetN
  • managed='no' # libvirt will create the device and set it up automatically or simply pass it

Progress Status

  • Code committed
  • Testing - QA
  • Documentation (Release notes - resolved issues, compatibility, known issues)

Metadata

Metadata

Assignees

No fields configured for Feature.

Projects

No projects

Milestone

Relationships

None yet

Development

No branches or pull requests

Issue actions