Make IP-addresses visible in prefixes of other VRFs

[Nefti-sama]

NetBox version

v4.1.1

Feature type

Change to existing functionality

Proposed functionality

If you create a prefix in VRF Global and create an IP-Address in VRF-2, the IP-Address should be visible in the prefix you created in VRF Global.
The same applies for prefixes and child-prefixes.

Use case

Why would one want to have that?

• Loopback Pools: Create a /24 prefix that is used for loopbacks in the whole network regardless of the VRF (common practice). That results in one prefix (maybe in Global) containing addresses of many VRFs
• Transfer networks between VRFs: If one creates a transfer network between 2 VRF's one address is in VRF-1 and the other one in VRF-2, but both are part of the same prefix.
• Transfer networks within VRF: One might have assigned a /24 prefix for all transfer networks in a system, regardless of the VRF. This network will be sliced in /31 (or any other size) prefixes that are a member of a VRF but should be visible under the /24 prefix

How could that be achieved (just brainstorming)?

• If an IP-address does not match any prefix in it's VRF but there is a prefix in "Global", make it part of this prefix
• Possibly add a checkbox "Catchall" to activate this feature for desired prefixes (would need a DB change)

Database changes

Depends

External dependencies

No response

[cruse1977]

If I log onto a router and show the global table, I don't see VRF routes. Likewise, in the main VRF's don't see other VRF routes, unless I specifically configure routing leaking - so your use case is against how most routers would work.

I think you need to flesh this out more, what you are describing is more akin to a l3 domain - but arguably its not VRF.

[Nefti-sama]

I think you are mixing up how the real world works (which is like you describe it besides the fact that I do indeed see the transfer-networks in both VRFs that it connects) and how a useful display of information in the netbox GUI could be done.
My usecase addresses the display of information in the GUI. If you are doing a bit of IP address management you are quite happy to see the information that I describe without clicking to 15 different places.
This could also be achieved with selecting a "display-parent prefix" for each prefix which would overwrite the automatic placement. The key point is the ability to display information in a compact way without sacrificing/altering parameters that could be used for automation

[PieterL75]

Current behavior is : if your prefix is set to 'global' then you will see all of the child prefixes and the IPs of all VRFs. once you select a VRF for the prefix, then only the child prefix and IPs of that VRF will be shown.

[DanSheps]

I think you are mixing up how the real world works (which is like you describe it besides the fact that I do indeed see the transfer-networks in both VRFs that it connects) and how a useful display of information in the netbox GUI could be done.

The main consumers of NetBox are Network Engineers. NetBox is designed to mimic the real-world where possible. To your proposal, I do not want my IP's that are in VRF ABC to be displayed in the global table, irregardless of whether or not there is containing active prefix.

My usecase addresses the display of information in the GUI. If you are doing a bit of IP address management you are quite happy to see the information that I describe without clicking to 15 different places.

This is your use case, but not the thousands of other users of NetBox.

This could also be achieved with selecting a "display-parent prefix" for each prefix which would overwrite the automatic placement. The key point is the ability to display information in a compact way without sacrificing/altering parameters that could be used for automation

I don't think we need to add any additional knobs for this. I don't think this is an option the vast majority of the community wants. That said, you are free to create a plugin to display this how you like using the existing models.

Current behavior is : if your prefix is set to 'global' then you will see all of the child prefixes and the IPs of all VRFs. once you select a VRF for the prefix, then only the child prefix and IPs of that VRF will be shown.

Not 100% true. Behaviour is:

If Prefix:

• is container
• solely encompasses addresses/prefixes (no "longer" match)
• is in Global VRF

it will display those IPs