When tuning an FCIP (Fibre Channel over IP) connection over a WAN with 300 ms latency, the following TCP parameters must be adjusted:
1. Modify the TCP retransmit time to account for WAN latency.
* The tcp min-retransmit-time 500command ensures that TCP waits at least 500 ms
before retransmitting lost packets, which is suitable for a high-latency WAN.
2. Set the TCP keepalive timeout to 15 seconds.
* The tcp keepalive-timeout 15command ensures that if no traffic is detected for 15
seconds, a keepalive probe is sent to maintain the connection.
3. Set the maximum number of TCP retransmissions to 5.
* The tcp max-retransmissions 5command limits retransmissions to 5 attempts before
the session is reset.