Dynamic Path Failover for AIX
Introduction
The Cambex FibreQuik™ Fibre Channel host bus adapters
provide attachment of Fibre Channel devices to PCI or Micro
Channel based servers. They support the SCSI-FCP protocol.
When used with the Cambex DPF (Dynamic Path Failover)
software, two adapters in a system provide greater throughput
and total protection from failure of a fibre channel component.
In addition, the Cambex AutoRecover daemon, cbxdpfar, will
automatically detect when a failed path has been repaired and
make it available as a standby path. For arrays that support
preferred paths, AutoRecover will automatically resume
operation on the repaired path, otherwise, an operator may
manually change paths to do load balancing.
Storage (SAN) and communications (LAN) networks have
resulted in a physical and logical separation between the storage
device (typically a SAN-connected RAID array), the storage
user (typically an Enterprise Server, which we will refer to
below as the server) and the administration station (typically a
remote workstation).
As storage systems have evolved from JBOD (just bunch of
disks) to complex shared RAID systems, the management
software has also grown in complexity. The following sections
describe the different levels of management software.
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