The network topology is router A and router B are directly connected with IP addresses configured on their physical interfaces
int gig 0/0/1 and gig0/0/2. The third
interface gig0/0/3 is configured as a layer-2 trunk port, and VLAN 12 is allowed to pass on router A and connect to router B's
interface gig 0/0/3 layer-2 trunk port. The IGP
ospf 100 is configured on both routers and enabled at
int gig 0/0/1 and gig0/0/2.
I have multiple IP addresses on the VLAN interface as below:
interface vlanif 12
ip address 188.8.131.52 255.255.255.224
ip address 184.108.40.206 255.255.255.224 sub
ip address 220.127.116.11 255.255.255.224 sub
ip address 18.104.22.168 255.255.255.224 sub
These are advertised in
router ospf by network statements in
ospf 100, but by mistake, network
22.214.171.124 0.0.0.31 was skipped when configuring the OSPF process network statement. The directly connected router B does not show the route of the subinterface IP addresses of
126.96.36.199, 188.8.131.52 and 184.108.40.206.
What is the concept of multiple IP addresses on a interface, and where it is used?
Why does OSPF fail to advertise the subinterface IP address when the primary IP address network
220.127.116.11 0.0.0.31 of VLAN 12 has been skipped in the OSPF configuration?