Users Guide

572 Fabric OS Administrator’s Guide
53-1002920-02
Requirements for trunk groups
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• If in-flight encryption or compression is enabled, you can have a maximum of only two ports per
trunk.
• An E_Port or EX_Port trunk can be up to eight ports wide. All the ports must be adjacent to
each other, in the clearly marked groups on the front of the switch.
Trunks operate best when the cable length of each trunked link is roughly equal to the length of the
others in the trunk. For optimal performance, no more than 30 meters difference is recommended.
Trunks are compatible with both short-wavelength (SWL) and long-wavelength (LWL) fiber-optic
cables and transceivers.
Trunking is performed according to the Quality of Service (QoS) configuration on the master and the
slave ports. That is, in a given trunk group, if there are some ports with QoS enabled and some with
QoS disabled, they form two different trunks, one with QoS enabled and the other with QoS
disabled. For more information on QoS, refer to “QoS zones” on page 419.
High Availability support for trunking
Trunking is a High Availability (HA) supported feature. The HA protocol for trunking is as follows:
• If trunking is disabled prior to the HA failover, it remains disabled after the HA failover.
• If trunking is enabled prior to the HA failover, it remains enabled after the HA failover.
Requirements for trunk groups
The following requirements apply to all types of trunking:
• All of the ports in a trunk group must belong to the same port group.
• All of the ports in a trunk group must meet the following conditions:
- They must be running at the same speed.
- They must be configured for the same distance.
- They must have the same encryption, compression, QoS, and FEC settings.
• Trunk groups must be between Brocade switches (or Brocade adapters in the case of F_Port
trunking). Brocade trunking is proprietary and is not supported on M-EOS or third-party switches.
• There must be a direct connection between participating switches.
• Trunking cannot be done if ports are in ISL R_RDY mode. (You can disable this mode by using
the portCfgIslMode command.)
• Trunking is supported only on FC ports. Virtual FC ports (VE_Ports or VEX_Ports) do not support
trunking.
Recommendations for trunk groups
To identify the most useful trunk groups, consider the following recommendations along with the
standard guidelines for SAN design:
• Evaluate the traffic patterns within the fabric.