primary hub in dmvpn learn route to tunn network hubsecondary-spokes

[mdzaf]

Hi,

I have dmvpn network with 2 hubs and spokes. Spokes have 2 separate mgre tunnel to the each hub (primary and secondary). For routing i am using eigrp.On the Primary Hub i see route to the network which is network between secondary hub and spokes and next hop is all spokes. In routing table is one route with 4 next hops which is maximum equal eigrp route. But in eigrp topology i see route to that network over any spoke (because every spoke network between itself and hub secondary advertise that route to the primary hub).

My question is it normal behaviour, or is there any best practice for this case because in the end i dont need route to the mgre network between hubsecondary-spokes or maybe i am making some mistakes?

Thank you   

[MHM Cisco World]

Tunnel 1 primary Hub <-> spokes have eigrp delay 100

Tunnel 2 backup Hub <-> spokes have eigrp delay 200

This make spoke use primary always until it down then it will shift to backup 

MHM

[mdzaf]

Hi,

Thank you for you answer. maybe i didnt explain well. From the perspektive of spoke i do that and in routing table spoke use primary tunnel, and standby when primary fails. My question is related to the hub1 and hub2. Spoke advertise tunnel2 network to the primary hub and spoke advertise tunnel1 network to the secondary hub. So both hubs have route to the tunnel network over all spokes in eigrp topology. For exampl hub1 learn that he can access tunnel2 network over 50spokes. I am attaching diagram.

[MHM Cisco World]

Interconnect between Hub why?

If spoke1 use hub1 need to connect to spoke2 which is connect to hub2' here come the role of interconnect 

So no need to do anything keep as it

If that what you ask for 

MHM

[mdzaf]

Hi sir,

I am not sure if we understand good again. I dont want interconnection. I am just asking is it normal behaviour that hub1 learn route to tunnel2 network(every spoke advertise tunnel network to the hub1 and hub2). In the end on the hub1 i have route to tunnel2 network over for example 50 spokes next hop in the eigrp adjacency table. And on hub2 i have route to tunnel 1 network over again for examole 50 spokes as next hop in the eigrp adjacency table. So i am asking to put like that and nothung change or maybe to filter to not maintain eigrp topology table for one route too big.

[MHM Cisco World]

Subnet 10.0.0.0/24 connect to spoke1 must know by hub1 from 

Spoke1 and hub2 (why from hub2 check my previous comment)

Is this subnet you ask for ?

MHM

[mdzaf]

Hi,

No. Please find attached image

[wajidhassan]

Yes, that's normal behavior with EIGRP in DMVPN. Each spoke advertises its tunnel network to both hubs, so Hub1 learns routes to Hub2's tunnel network via spokes. To clean this up, consider filtering those routes with EIGRP route-maps or summarization.

[mdzaf]

Hi,

If stay like this any consequence? Also regarding to filtering did you mean to filter on both hubs?

[MHM Cisco World]

I dont like the two Hubs not interconnect and can I ask why you not interconnect it?

For filter we usually use stub in spoke 

We make spoke stub and only send 

Connected & summary 

But since hub1 know prefix of second dmvpn from spoke we can use leak-map and filter all second dmvpn prefix 

MHM

[mdzaf]

Hi,

Hubs is connected to the different ISP. It is connected via LAN. If communication from spokes over HUB1 goes down (device stopped or ISP), everything move through HUB2. I solved on the way creating prefix list for tunnel network, and with distribute list apply on router eigrp configuration in in direction so now i dont have on hub1 tunnel 2 network, and also on hub2 i dont have tunnel1 network.

[MHM Cisco World]

Sure you can use distribute list' I prefer stub if you have time later check it.

Why I am asking about interconnect' 

If spoke1 need to connect to spoke2 

But spoke1 have health wan to hub1 and spoke2 have health wan to hub2 how you can achieve that.

Interconnect not need if you not need spoke to spoke connect 

MHM

[mdzaf]

Hi,

There is no chance that spoke1 have health want to hub1 and spoke2 have healt wan to hub2 (i mean spoke have 2 tunnel but with modification of delay on spokes  i always choose primary  hub1 from all spokes, Spokes have only  1 phsyical wan). If wan to hub1 is healt all spokes goes through hub1, if not everyone goes through hub2.

Spokes talks with each other directly. They dynamicly establish tunnel by help on NHRP. 

[MHM Cisco World]

How you guarantee that all spokes will use same hub.

We talking about WAN issue not hub failed 

MHM

[mdzaf]

Hi,

on primary tunnel going to hub1 i dont modify delay. I modify and make delay higher on secondary tunnel. So spoke always use route to DC network advertise by hub1 because it has lower cost. When hub1 failed, or wan connection on hub1 failed, eigrp will insert route pointing on tunnel2