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Refer to the exhibit.
BGP and EIGRP are mutually redistributed on R3, and EIGRP and OSPF are mutually redistributed on R1. Users report packet loss and interruption of service to applications hosted on the 10.1.1.0724 prefix. An engineer tested the link from R3 to R4 with no packet loss present but has noticed frequent routing changes on R3 when running the debug ip route command. Which action stabilizes the service?
After redistribution, R3 learns about network 10.1.1.0/24 via two paths:
+ Internal BGP (IBGP): advertised from R4 with AD of 200 (and metric of 0)
+ OSPF: advertised from R1 with AD of 110 (O E2) (and metric of 20)
Therefore R3 will choose the path with the lower AD via OSPF
But this is a looped path which is received from R3 -> R2 -> R1 -> R3. So when the advertised route
from R4 is expired, the looped path is also expired soon and R3 will reinstall the main path from R4.
This is the cause of intermittent connectivity.
We can solve this problem by denying the 10.1.1.0/24 prefix from being redistributed into OSPF on
R1. So R3 will not learn this prefix from R1.
Or another solution is to place an OSPF distribute-list inbound on R3 to block the 10.1.1.0/24 prefix
from being advertised back to R3.