EIGRP MULTICAST ADDRESS query

[ajay kondapalli]

Hi,

Can any one clarify my doubt , this is regarding EIGRP route advertisements.

Generally EIGRP uses multicast address to advertise subnets to its neighbors. If we have 1 Head office router connected to 4 branch office routers.

And if we don't want to send updates to one of the Branch routers through Multicast address 224.0.0.10, instead of that we want to send it as Unicast .

( All the remaining routers should get updates by multicast address only )

Can we achieve this ? If so how can we do that.

Thanks,

Ajay

[Giuseppe Larosa]

Hello Ajay,

you need to use neighbor command and you need a dedicated logical interface for that neighbor, if you have a single p2mp interface for all neighbors  you should check what happens when using the neighbor command only for that specific neighbor if it overrides the default multicast hello you are fine

see

http://www.cisco.com/en/US/docs/ios-xml/ios/iproute_eigrp/command/ire-i1.html#GUID-7D3E87EC-3482-4EAA-BED7-BB5777C772FD

Hope to help

Giuseppe

[ajay kondapalli]

Thanks,

Can we assume same to OSPF also.  We can use neighbor command in OSFP to override multicasting ?

Thanks,

Ajay

[cadet alain]

Hi,

yes you can unicast hellos in OSPF like in EIGRP and this feature is also supported in RIP configs.

this was not created to override multicast but to enable EIGRP or OSPF in networks with no multicast support,

once you configure the neighbour command the router will stop sending but also receiving multicast hellos on the interface configured in the command so it must be configured on both sides in EIGRP.

Regards.

Alain

[RIAZSHAIKH]

Hi,

You can also use Passive Interface to stop Multicast on interfaces. :)

[Hossein Forghani]

you should passive interface then use neighbor command.
Good luck

[RIAZSHAIKH]

Thanks