Traffic from the managed network will leak into the management network via the gateway router interface connected to the OOBM backbone.
If the gateway router is not a dedicated device for the OOBM network, several safeguards must be implemented for containment of management and production traffic boundaries such as using interface ACLs or filters at the boundaries between the two networks.
Configure the OOBM gateway router interface ACLs to ensure traffic from the managed network does not leak into the management network.
Examine the egress filter on the OOBM interface of the gateway router to verify that only traffic sourced from the management address space is allowed to transit the OOBM backbone. In the example configurations below, the 10.1.1.0/24 is the management network address space at the enclave or managed network and 10.2.2.0/24 is the management network address space at the NOC. IOS interface Serial0/0 description to_OOBM_Backbone ip address 10.1.20.3 255.255.255.0 ip access-group 101 out interface Fastethernet 0/0 description Enclave_Management_LAN ip address 10.1.1.1 255.255.255.0 interface Fastethernet 0/1 description to_our_ServiceNet ip address 172.20.5.2 255.255.255.0 ! access-list 101 permit ip 10.1.1.0 0.0.0.255 10.2.2.0 0.0.0.255 access-list 101 deny ip any any log