Adaptec MAN-00005-UG, Installation And User Manual

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© 2003, Adaptec, Inc.
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function should remain enabled during normal controller operation. A controller
reset is required before this parameter takes effect.
Enable background initialization: When enabled, this option allows a single logical drive or multiple logical drives to
be initialized as a background operation while reads and writes are being performed.
Background initialization is invoked automatically upon receipt of the first read/
write command from the host. When the controller starts up or after a configuration
changes, background initialization automatically initializes any un-initialized
system drives one at a time.
The secondary option, “ Start BGI on host write ” determines when the background
initialization begins. If this box is checked, initialization of new logical drives starts
when the controller receives a write command from the host.
The controller firmware allows the background initialization to be paused during a
controller reset. The background initialization progress is saved to NVRAM. After
the controllers have restarted, the background initialization resumes close to where
the pause occurred.
Background initialization is paused by any of the following operations: initialize
system drives (foreground initialization); consistency check; automatic rebuild;
array expansion; and logical drive expansion. If one of these operations is started
while background initialization is running, background initialization is paused until
the interrupting operation is complete. At that point, background initialization
continues initializing the system drive that it was initializing from the point of
interruption. If the interrupting operation resulted in the system drive being
initialized, however, background initialization skips that system drive and searches
for the next un-initialized system drive and begins initializing.
Performance is degraded during background initialization because every write
operation requires access to all drives in the RAID group. Once all system drives
have been initialized, performance is restored.
Topology: Select one of the following topologies from the drop-down list.
Multi-Port. All ports are active. This topology does not provide transparent
failover/failback and requires an alternate path driver in the host.
Multi-TID. All ports are active. This topology is supported on SANbloc hardware.
This topology provides transparent failover/failback and should not be used in
conjunction with an alternate path driver.
Notes:
•
A controller reset is required to make a change to this option take affect.
• Only those topologies that are supported on the controller are listed in the drop-
down menu.
• Inactive Port. Controller 0 port 0 and controller 1 port 1 are active. During
failover, the inactive port on the partner takes over for the active port on the
failed controller.
Note:
•
Master/Slave. Both ports on controller 0 are active. During failover, controller
1 assumes control.
Side affects of changing topologies:
•
When changing from inactive port to master/slave, logical drives associated
with controller 1 port 1 are reassigned to controller 0 port 1.
• When changing from master/slave to inactive port, port mappings associated
with controller 0 port 1 are reassigned to controller 1 port 1.
• When changing from master/slave or inactive port to Multi-TID or MultiPort,
the inactive ports are enabled and all port mapping remains unchanged.