Feature pages are design documents that developers have created while collaborating on oVirt.

Most of them are outdated, but provide historical design context.

They are not user documentation and should not be treated as such.

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Host Networking Api


  • Name: Moti Asayag (masayag)
  • Email:

Current Status

The current host networking api (up to ovirt-engine-3.6) suffers from various limitations:

  • A mix of the physical and the logical network configuration
    • Exposing vlan device implementation to the user
    • Using ‘Sync Network’ feature requires to find the specific interface which carries the network
  • A Cumbersome request format for ‘setup networks’:
    • creating vlan devices
    • a complex input structure to represent the expected configuration
  • The attach/detach network isn’t the RESTFul way to modify the interface
  • Cannot support a host only network (a network without a nic)
    • Cannot support a dynamic (external) networks

Proposed Solution

Introduce <network_attachment> element which describes how the network is configured on the host:

  • network - which logical network is connected to the host
  • host_nic - an optional sub-element which described the underlying interface
    • When not provided, implies the network is a nic-less network (not supported in 3.6)
    • Can specify an unused nic or a bond (either existing bond or bond to create from unused nics).
  • ip_address_assignments - the ip configuration (ipv4/ipv6, boot protocol and addresses)
  • properties - network custom properties
  • reported_configuration - read-only element, returned only when the network is out-of-sync with the logical network definition, listing the specific out-of-sync properties.

The ip_address_assignments representation is:

     <ip address="…" netmask="…" gateway ="…"/>
     <ip address="…" netmask="…" gateway ="…"/>
     <ip address="…" netmask="…" gateway ="…" version="6"/>

A new link_aggregation element is added to abstract the implementation:

       <host_nic id="833ebaeb-0988-4bd5-b860-e00bcc3f576a"/>
       <host_nic id="782e8199-984e-407f-b242-3d6c7dc2f7b7"/>

The link_aggregation element will be used from within the host_nic element for bonding devices.

Network attachments sub-collection of the nic resource

  • A collection of network attachments that are attached to a specific physical interface or a bond:


  • Supported actions:

    1. GET returns a list of networks attached to the nic
    2. POST attaches a network to the nic

Setupnetworks API of the host resource

  • A multi-network configuration action to support complex network settings (i.e. cross nics actions: move network from one nic to another or create network on bond)


  • Supported actions:
    • POST - expects a relative change to be applied on the host, using PATCH behaviour.
  • Request structure:
   <modified_bonds />
         <removed_bonds />
   <modified_network_attachments />
   <removed_network_attachments />
   <check_connectivity />
   <connectivity_timeout />
  • modified_bonds - describes bonds to create or to update, those bonds could be referred by name from the network_attachment element
  • removed_bonds - id list of bonds to be removed
  • modified_network_attachments - describes which networks should be configured (added or updated) on the host.
    • When host nic is provided, the network will be configured on it
    • When host nic is omitted, the network will be configured as a nicless network (not supported in 3.6)
    • When a nic is changed, the network will be reconfigured on the new nic (move network from nic to nic). Network id cannot be changed from one to another as a part of update. Network can be identified by id or name just like bond.
  • removed_network_attachments - id list of network attachments to remove
  • synchronized_network_attachments - network attachment list to be synchronized with nic

Network attachment resource under nic


  • Supported actions:
    1. GET - returns a specific network attachment; attaches network to the nic, when nic id is provided.
    2. DELETE - deletes network attachment; detaches a network from the nic
    3. PUT - updates the network network attachment

Network statistics sub-collection (optional)


  • Supported actions:
    1. GET returns a specific statistics for a network attachment(if reported) which is attached to the nic
  • We can implement a new API in this context to reflect the total rx/tx instead of a processed measurements.

Host Network attachments sub-collection

Introducing new sub-collections to reflect the host network configuration:

  • A collection of network attachments which represent how the network is provisioned on the host


  • Supported actions:
    1. GET returns a list of networks attachments configured on the host
    2. POST provision a network on the host

Where the networkattachment element will omit the host_nic element from the request. If provided, must be in sync with one provided on URL path

Host Network attachment resource


  • Supported actions:
    1. GET returns a specific network configured on the host
    2. PUT Update a network configured on the host, where modifying the nic indicates network will be configured on the new network device.
    3. DELETE removes a network from the host

Current Host Networking API (up to ovirt-engine-3.5)


  • GET - list of network interfaces (GetVdsInterfacesByVdsId)
  • POST - creates a bond (AddBond)


  • POST - performs setup networks action (SetupNetworks)


  • GET - gets a specific network interface (GetVdsInterfacesByVdsId)
  • DELETE - removes a bond (RemoveBond)
  • PUT - updates a network which is attached to the specific network interface, aka mini-setup networks (UpdateNetworkToVdsInterface)


  • POST - adds a network to a nic (AttachNetworkToVdsInterface)


  • POST - removes a network from a nic (DetachNetworkFromVdsInterface)


  • GET - list the statistics of the specific network interface

Network labels related actions are listed at Features/NetworkLabels#REST.

What should be deprecated?

  • The network element in host_nic is replaced by networkattachments subcollection:


   <network />

is replaced by:



The vlan devices will be hidden from the list of /api/hosts/{host:id}/nics and will be represented as a networkattachment element of the underlying nic.

  • Deprecated: /api/hosts/{host:id}/nics/setupnetworks
     <network id="..."/>
  • Is replaced by: /api/hosts/{host:id}/hostsetupnetworks

Request should contain only nics or bonds (no vlans).

  • Deprecated Host nics actions:

    /api/hosts/{host:id}/nics/{nic:id}/attach is replaced by POST request to /api/hosts/{host:id}/nics/{nic:id}/networkattachments


/api/hosts/{host:id}/nics/{nic:id}/detach is replaced by DELETE request to: /api/hosts/{host:id}/nics/{nic:id}/networkattachments/{networkattachment:id}

  • Updating network interface

PUT on /api/hosts/{host:id}/nics/{nic:id}/ the action semantics is changed to edit bond only

is replaced by

PUT on /api/hosts/{host:id}/nics/{nic:id}/networkattachments/{networkattachment:id}

Behaviour Change

Since the Network Attachment is the entity for describing a network attachment to the host, and it requires to be associated to an existing network on the data-center, unmanaged networks handling will be done differently than <= ovirt-engine 3.5. Unmanaged networks are networks which are reported by vdsm (hence those networks are reported by libvirt and have the expected prefix of “vdsm-“), but are not identified as networks on the cluster on which the host resides.