Which BGP feature should be used to avoid high memory utilization on a router?
A.
soft-reconfiguration
B.
route refresh
C.
BGP communities
D.
full-mesh BGP peering
Explanation:
BGP routers have enormous routing tables so it uses much memory to proceed these routes.
When a BGP policy is changed, the BGP session needs to be reset for the policy to take effect.
But the resetting results in route churn and route flapping. There are two ways to clear a BGP
session without resetting the TCP session between them (this is often called “soft reset”):
Soft-reconfiguration: stores all received (inbound) routing policy updates without modification in
a table so that when a new filter is applied, the router will use this table to calculate the changes
without resetting the TCP session between the two BGP peers . This is a memory-intensive (high
memory utilization) method and is not recommended.
Route-refresh: allows a BGP router to request a remote peer resend its BGP Adj-RIB-Out. This
allows the BGP router to reapply the inbound policy. The route-refresh capability requires no extra
memory on the local router