This scenario combinessession continuity,multiple protocols (HTTP and FTP), andHA failover behavior, which directly implicatespersistence handling across devices and services.

Key Requirements Breakdown

Samepool member for entire session

Session must survivefailover

Session must spanmultiple services (HTTP and FTP)

Why Persistence Mirroring + Match Across Services Is Required

Persistence Mirroring

Ensurespersistence records are synchronizedfrom the active BIG-IP to the standby BIG-IP.

Without mirroring:

After failover, the standby device hasno persistence table

Clients are load-balanced again

Sessions break, forcing users to restart

Persistence mirroring is essential forsession continuity during failover

Match Across Services

Allows asingle persistence recordto be shared acrossmultiple virtual servers / protocols

Required when:

HTTP and FTP must use thesame pool member

Multiple services are part of a single application session

Together, these settings ensure:

Persistence survivesdevice failover

Persistence is honoredacross HTTP and FTP

Why the Other Options Are Incorrect

A. Cookie persistence and session timeoutCookie persistence only applies to HTTP and does not address FTP or failover synchronization.

B. Stateful failover and Network Failover detectionStateful failover applies toconnection state, notpersistence records, and does not link HTTP and FTP sessions.

D. SYN-cookie insertion threshold and connection low-water markThese are DoS / SYN flood protection settings, unrelated to persistence or HA behavior.