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Dynamic tracking of Fibre Channel adapters

AIX 5.2 provides support for Dynamic Tracking of Fibre Channel devices. In previous AIX releases, the user was required to unconfigure the FC storage device and adapter device instances before making changes on the SAN that might result in an N_Port ID (SCSI ID) change of any remote storage ports.


If Dynamic Tracking for FC devices is enabled, the FC adapter driver will detect when the Fibre Channel N_Port ID of a device changes, and will reroute traffic designated for that device to the new address, while the devices are still online. Examples of events that can cause an N_Port ID to change are moving a cable between a switch and storage device from one switch port to another, connecting two separate switches via an Inter-Switch Link (ISL), and possibly rebooting a switch.

Dynamic tracking of FC devices is controlled by a new fscsi device attribute, named dyntrk. The default setting for this attribute is no. Setting this attribute to yes enables dynamic tracking:

{node1:root}/-> chdev -l fscsi0 -a dyntrk=yes

Dynamic tracking logic is invoked when the adapter driver receives an indication from the switch that there has been a link event involving a remote storage device port.

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