Cisco DS-C9216I-K9, Руководство по настройке

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24-14
Cisco MDS 9000 Fabric Manager Switch Configuration Guide
OL-7753-01
Chapter 24 Configuring IP Storage
Configuring FCIP
FCIP configuration options can be accessed from the switch(config- profile)# submode prompt.
Configuring TCP Listener Ports
The default TCP port for FCIP is 3225. You can change this port using the port command.
Configuring TCP Parameters
This section provides details on the TCP parameters that can be configured to control TCP behavior in
a switch. The following TCP parameters can be configured.
Minimum Retransmit Timeout
The tcp minimum-retransmit-time option controls the minimum amount of time TCP waits before
retransmitting. By default, this value is 200 milliseconds.
Keepalive Timeout
The tcp keepalive-timeout option enables you to configure the interval between which the TCP
connection verifies if the FCIP link is functioning. This ensures that a FCIP link failure is detected
quickly even when there is no traffic.
If the TCP connection is idle for more than the specified time, then keepalive timeout packets are sent
to ensure that the connection is active. This command can be used to tune the time taken to detect FCIP
link failures.
The first interval during which the connection is idle is 60 seconds (default). When the connection is idle
for 60 seconds, 8 keepalive probes are sent at 1-second intervals. If no response is received for these 8
probes and the connection remains idle throughout, that FCIP link is automatically closed.
Only the first interval (during which the connection is idle) can be changed from the default of 60
seconds. This interval is identified using the
keepalive-timeout
option. The valid range is from 1 to 7200 seconds.
Maximum Retransmissions
The tcp max-retransmissions option specifies the maximum number of times a packet is retransmitted
before TCP decides to close the connection.
Path MTU
Path MTU (PMTU) is the minimum MTU on the IP network between the two end points of the FCIP
link. PMTU discovery is a mechanism by which TCP learns of the PMTU dynamically and adjusts the
maximum TCP segment accordingly (RFC 1191).
By default, PMTU discovery is enabled on all switches with a default timeout of 3600 seconds. If TCP
reduces the size of the max segment because of PMTU change, the reset-timeout specifies the time after
which TCP tries the original MTU.