There are cases where it's useful to add export only and import only
route-targets to a virtual-network. For example, this can be used to
create hub-and-spoke topology for a collection of virtual-networks.
Note that the notion of export only and import only targets for routing
instances is already supported and used under the covers for service
chaining. This enhancement is to support export/import-only targets
for VNs.
Currently route-targets for a VN are configured using route-target-list
property which is of type RouteTargetList. RouteTargetList is simply a
list of route-target strings.
A simple way to add desired functionality would to be add a couple more
properties called export-route-target-list and import-route-target-list.
Route targets configured using route-target-list property will continue
to be treated as import and export targets for backward compatibility.
UI should allow user to specify target as Import and Export, Export Only
or Import Only. It needs to add the targets to appropriate property i.e.
route-target-list, export-route-target-list or import-route-target-list.
Schema transformer should process the [export|import]-route-target-list
and add those targets to the default routing-instance for the VN, with
the appropriate type. Further, if there's a service chain starting at
the VN, the export-only targets for the VN should also be applied to
the first service routing-instance in the chain.
Note that it may not be sufficient to configure import and export targets
on VNs in order to communication, even though the routes will be imported
into the VNs. User will additionally need to configure policy so that the
right ACL can be generated for the VN. Policy configuration may reduce the
need for user to configure import-only targets in many cases since policy
has pretty much the same effect. However, import-only targets should still
be supported to allow maximum flexibility.
Review in progress for https:/
Submitter: Sachin Bansal (<email address hidden>)