HP XP P9500 Storage - Manual (Page 67)

WWN of Port Controller Model
XXXXXXXXXXXXXXX9
XXXXXXXXXXXXXXXA
XXXXXXXXXXXXXXXB
XXXXXXXXXXXXXXXC
XXXXXXXXXXXXXXXD
XXXXXXXXXXXXXXXE
XXXXXXXXXXXXXXXF
Note: In WWNs, "X" is an arbitrary number or character. The ports in a physical storage system have the identical
value.
When the model of HUS/AMS/WMS storage system is changed, the WWN of the port is changed
as well. If the HUS/AMS/WMS storage system is used as an external storage system, the mapped
external path may be blocked. To correct this problem, you can delete the mapping of the external
path and remap it to use the blocked external path. See
(page 50) for detailed information on
remapping.
Identifying logical volumes using Characteristic1
The Characteristic1 value is the internal LUN number of the LUNS from the AMS/WMS.
Caution on using the power savings option
When an HUS 150, HUS 130, HUS 110, AMS 2500, AMS 2300, AMS 2100, or AMS 2010
storage system is connected as an external system with the Power Savings option is enabled, do
not access external volumes from a host if the external volumes are spinning down. This prevents
the external volume status from changing to Blockade.
If external volume status changes to Blockade, the volume is automatically restored in several hours.
You can also manually restore the external volumes by reconnecting the external volume.
AMS 2000 series guidelines
•
Avoid unnecessary load to the external storage system. Path mode between storage systems
is Multi mode; therefore, when many external paths and mapping volumes are mapped, the
load to the external system is high; some commands from host to the HP P9500 or from the
HP P9500 to the external system may time out. To keep the proper load, the following is
recommended.
◦ Specify two external paths. Set the paths to the ports of each controller of the AMS 2000
series system.
◦ Set the queue to 500 or fewer commands issued at the same time from a AMS 2000
series system. The formula to calculate the number of queue commands per system is as
follows.
(number of queues) x (number of external paths) x (number of
concurrent external volume commands) < 500
For more information about command queue settings, see Editing external WWN settings
(page 39) .
•
When using external volumes for replication, the copy operation needs to be distributed to
two or more RAID groups.
There is an upper bound to the number of pairs that can be used for initial copy or
resynchronization. Therefore, the copy operation may focus on a specific RAID group according
to the order of the operation when it is performed to two or more external volumes.
If the copy operation focuses on a specific RAID group, then the AMS 2000 drive could
bottleneck.
HUS/AMS/WMS 67