Hi there,
I was wondering if there is any elegant solution that allows to share the available download bandwidth (hub to spoke) of a spoke site between multiple VRFs on a DMVPN spoke router.
The scenario is as follows:
Each of my spoke routers implements multiple VRFs that should share the available site bandwidth.
In the upload direction this can be easily* achieved by binding the QoS policy to the physical interface towards the provider the DMVPN tunnels are built over.
However, in the other direction, namely hub-to-spoke, it get's more complicated.
If the per-tunnel QoS for DMVPN feature is implemented on a per tunnel basis, I would either have to allocate the overall spoke bandwidth between the different VRFs or potentially oversubscribe by instructing the hub that the available bandwidth of each of the VRF-specific tunnels towards the spoke equals to the whole spoke bandwidth.
It seems that the only possible way to achieve the utilization of the per-tunnel QoS feature so that the spokes bandwidth is shared between multiple VRFs is to build an additional "underlay" DMVPN that acts as the transport for the other VRF-specific DMVPNs.
Simplified illustration:
Provider Transport {
Underlay DMVPN (Transport for VRF-specific DMVPNs) {
VRFa-DMVPN
VRFb-DMVPN
VRFc-DMVPN
}
}
I'm also wondering if IWAN (PfR) would work in such a scenario, i.e. DMVPN (VRF-specific, PfR controlled) over DMVPN (transport).
Any feedback or ideas are highly appreciated :-)
Bfn,
Stephan
*There is also no means of control for spoke-to-spoke traffic not to potentially oversubscribe other spokes with lower access bandwidths.
