Catalyst 3560 Protected Port/Private-vlan question

[situwayne]

I run into this from lab experiment.

Equipment used: Cat3560 EMI, (4) 3640 routers

R1 and R2 are connected to switchports in vlan 12

R3 and R4 are connected to switchports in vlan 100

R1 ? 131.1.12.1/24

R2 ? 131.1.12.2/24

R3 ? 131.1.100.3/24

R4 ? 131.1.100.4/24

When Eigrp is configured on all 4 routers, all routers are experiencing ?IP-EIGRP(Default-IP-Routing-Table:100): Neighbor x.x.x.x not on common subnet? error messages.

This is not a problem with Eigrp and it can be fixed with no eigrp log-neighbor-warnings.

The question is how can I configure the cat3560 to stop sending multicast to all switchports except those are within the same vlan?

thanks

[gpulos]

you could use ACLs to control the multicast traffic if you need.

also, you should identify why the NeighborNotOnCommonSubnet is being sent.

as far as eigrp is concerned, there is an eigrp neighbor advertising a subnet that the receiving eigrp router sees as sourced by an interface not on the recieving routers subnet.

please see this link for more info on the eigrp common subnet message:

http://www.cisco.com/en/US/tech/tk365/technologies_configuration_example09186a0080093f09.shtml

please see this link for more info on ACL configuration for the 2950:

http://www.cisco.com/en/US/products/hw/switches/ps628/products_configuration_guide_chapter09186a00804cc117.html