Virtual chassis support for virtual machines (VM)

[netgab]

Hi community,

starting a discussion here, before posting a feature request, because I'm quite unsure:

• if there's an audience for this except for myself
• what needs to be done in terms of DB changes, because this is required in a feature request

Proposed functionality

Extend the virtual chassis functionality to include virtual machine objects.
As for now, virtual chassis members are devices (dcim.devices).

Use case

There's a growing number of physical network device platforms, which may be virtualized.
One example is Cisco Catalyst 9800 WLAN controllers, which may be installed on physical chassis and in virtual environments like vSphere or KVM. The clustering mode (SSO) is supported in virtual environments as well.

Database changes

Unsure about that one. I only speak REST-API and no database (sorry) ;)

But I guess that the virtual-chassis object needs to be modified to allow virtual machine ids as members (e.g. master_id)

The virtual machine object model needs to be extended to relate virtual chassis to the object (vc_* and virtual_chassis_* attributes)

External dependencies

None

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There has already been an issue for this, but it was abandoned (#18891)

[jeremystretch]

Just so you're aware, this is not something we'd accept in core. A virtual chassis by definition is a set of physical devices.

[netgab]

Hi @jeremystretch,

thank you for the quick reply.

[...] this is not something we'd accept in core. A virtual chassis by definition is a set of physical devices.

Ok - good to know. What's the consequence of this statement?

That this idea might not be implemented using the virtual-chassis model, right? So a new model whould be needed like virtual-machine-cluster or virtual-machine-stack (or another, meaningful name).

Or is this - from a functional side (not the implementation) a bad idea at all?

Let's see if there are people who like this idea, or if I am the only one who is interested in something like this (because it would model real-world use cases ;) )

[Zombie-Toad]

I don't know if I get this right but do you want to create a "chassis" with a physical and a virtual device?
If so, "Cluster" would be the way to go, I think.

[netgab]

Hi @Zombie-Toad,
sorry for not making this clear in my initial post, but an interesting question.
I meant a pure device or virtual-machine virtual chassis. Not a mix.

However, why not :) - but I don't know any network device vendor, which allows to mix physical and virtual chassis....

[Zombie-Toad]

For pure device or virtual-machine I would also use a cluster. Let's say you have two WLAN controllers running in active-passive mode, you could create a Cluster Type "HA-Cluster (active-passive)". Then create a Cluster "WLAN-Controllers" and assign both VMs to that cluster. You can also create a "Cluster Group" for your virtual environment and assign multple clusters to this.

[netgab]

Could work ... although I use the cluster model exclusively for Virtual Machine Hypervisors (and I guess that's the intended use case for this).
Furthermore, the virtual chassis object is perfect for the integration with Ansible nb_inventory and the virtual_chassis_name property.
In the Ansible inventory, the inventory_hostname becomes the virtual chassis name. The primary member is the source for config context and other attributes.

Example:

• Virtual chassis name: my_wlc
• Members:
  • Virtual machine: my_wlc-1 (with position 1)
  • Virtual machine: my_wlc-2 (with position 2)

In the Ansible inventory, I'll get a device (Ansible host) with the name my_wlc and the properties of my_wlc-1