Brocade Network Advisor SAN User Manual v12.1.0 User Manual
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Brocade Network Advisor SAN User Manual
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Adding an FCIP circuit
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6. Enter the MTU Size.
For SAN traffic, the largest possible MTU (Maximum Transmission Unit) size is generally the
most efficient. Enter a value between 1260 and 2348 for the 4 Gbps platforms and between
1260 and 1500 for the 8 Gbps platforms. MTU rates must match on both ends of the tunnel.
If you have an active connection between switch one and switch two, click Verfiy IP
Connectivity under Switch One Settings to test the connection. To determine a suggested size,
packets are sent across the FCIP tunnel, starting at the largest possible size packet that can
be sent over IP. If a valid connection response is not received, a smaller packet is sent. This
continues until a valid connection response is received, and that size becomes the suggested
MTU. MTU settings must match at both ends of the tunnel, and the setting specified under
Switch One Settings is automatically applied to switch two.
NOTE
Verify IP Connectivity button function requires an active IP connection. The button is not
available for the Add FCIP Circuit and Edit FCIP Circuit dialog boxes for 8 Gbps Extension
platforms.
7. If a VLAN ID is used to route frames between the switches over the physical connection, enter
the VLAN ID under Switch One Settings. You must assign the VLAN ID to both switches. You can
assign the same or different VLAN IDs to each switch.
The VLAN ID is an integer value between 1 and 4094 which sets the VLAN tag value in the
header assigning the traffic to that specific VLAN. Layer two class of service (L2CoS) values
may be assigned to establish traffic priorities over a VLAN. This is done as an Advanced
Setting.
8. The Metric option is used to identify a failover circuit. By assigning a non-zero metric (1), you
identify the circuit as a failover circuit. By default, a circuit is assigned a metric of 0. If a metric
0 circuit fails, FCIP trunking tries first to retransmit any pending send traffic over another circuit
with a metric of 0. If no circuits with a metric of 0 are available, then the pending send traffic is
retransmitted over any available circuit with a metric of 1.
The default metric value for a crossport circuit configuration will be 1. If a failover circuit is
created with a metric of 0, it will be used for load balancing and not for failover.
9. Designate a Failover Group for the circuit from 0 to 9. A value of 0 designates the default
failover group or no failover group.
With Circuit Failover Groups you can better control which metric 1 circuits will be activated if a
metric 0 circuit fails. For this feature, you define a set of metric 0 and metric 1 circuits that are
part of the same failover group. When all metric 0 circuits in the group fail, metric 1 circuits will
take over data transfer, even if there are metric 0 circuits still active in other failover groups.
For more information on Circuit Failover Grouping, refer to
NOTE
Failover Group will only be enabled when the switch or chassis is using Fabric OS v7.2 and
later.