Unusual behavior in DMVPN Phase1 - OSPF configuration

[Ariyarathna]

As per the recommendation Hub router should be the DR and all spokes should be DROTHER by making OSPF priority of the tunnel interface  in Spokes as 0.I am just trying to test the result when spoke is become DR and Hub is become BDR.  

Anyone please help me to understand the concept behind following observations.

1. As per my understanding spoke 1 (DROTHER) should exchange  OSPF routes with Hub (BDR) but in this case SPOKE1 can not access DR (Spoke2).But as per the above emulation when I check the routing table Hub route (BDR)r will not learn the Spoke1 (DROTHER) subnet .

2.When I clear OSPF process of Spoke 1 Hub router role perspective to the Spoke 1 change to DR from BDR.

But Hub is remain as BDR.

Please help me to clarify above confusions. Thank you very much for your valuable time....

[balaji.bandi]

Can you also post the configuration, if the Spokes set IP ospf pri 0, they will not elect DR or BDR

Make sure the OSPF  network type -  ip ospf network point-to-multipoint or broadcase on Hub

[Ariyarathna]

Hi balaji,

Thanks for the reply. My intention is to make Hub as BDR and  Spoke as DR. So I have change OSPF priority as following.

Hub - 100

Spoke 2 - 255

Spoke 1 - 0

Thanks,

Manoj

[balaji.bandi]

My intention is to make Hub as BDR and  Spoke as DR. 

Why ? that is not the recommended design any of Live deployment i see.

HUB is the one where HQ sits, why you like all transit traffic go via spoke ? i do not understand what is your intention here ? Spoke to be DR  ?

[Ariyarathna]

Hi Balaji,

My intention is to study behavior of the OSPF when  Spoke is not DR. This is not a real world scenario.

Thanks,

manoj

[balaji.bandi]

If the Lab, what is the exit Point of the network and routing point of view? if the Spoke become DR?

[Georg Pauwen]

Hello,

post the full configs (sh run) of all routers so we can lab this...

[Ariyarathna]

Hi Georg,

Please find the configuration files.

[paul driver]

Hello
I think It has nothing to do with dmvpn its just ospf design, clearing the process from the DR rtr wont make it then a BDR when the adjacency is reestablished, however if  you reset the ospf process from the current BDR rtr then the DR election will change.