HP 3PAR OpenVMS Implementation Guide (763874-002)

2/-idle-arbff - IDLE in Link Init, ARBFF as fill word (SW)
3/-aa-then-ia - If ARBFF/ARBFF failed, then do IDLE/ARBFF
HP recommends that you set the fill word to Mode 3 (aa-then-ia), which is the preferred mode
using the portcfgfillword command. If the fill word is not correctly set, er_bad_os
counters (invalid ordered set) increases when you use the portstatsshow command
while connected to 8 G HBA ports, as they need the ARBFF-ARBFF fill word. Mode 3 will
also works correctly for lower-speed HBAs, such as 4 G or 2 G HBAs.
For more information, see the Fabric OS command Reference Manual and the FOS Release
Notes.
• The Cisco switch ports that connect to HP 3PAR StoreServ Storage system ports or host HBA
ports must be set to AdminMode = FX and AdminSpeed = auto port, with the speed set
to auto negotiate.
Target port limits and specifications
To avoid overwhelming a target port and to ensure continuous I/O operations, observe the following
limitations on a target port:
• Maximum of 64 host OS ports per HP 3PAR StoreServ Storage system port, with a maximum
of 1,024 host OS ports per HP 3PAR StoreServ Storage system.
• I/O queue depth on each HP 3PAR StoreServ Storage system HBA model must be:
HP 3PAR host port 8G: 3276 (V400/V800 systems only)◦
◦ The I/O queues are shared among the connected host OS HBA ports on a first-come,
first-serve basis.
◦ When all the queues are in use and a host HBA port tries to initiate an I/O request, it
receives target queue full response from the HP 3PAR StoreServ Storage system
port. This condition can result in erratic I/O performance on each host OS. If this condition
occurs, each host OS must be throttled so that it cannot overrun the HP 3PAR StoreServ
Storage system port's queues when all the host OS are delivering their maximum number
of I/O requests.
NOTE: When host OS ports can access multiple targets on fabric zones, the target number
assigned by the host driver for each discovered target can change when the host OS is booted
and some targets are not available in the zone. This situation may change the access point of the
device node during a host OS reboot. This occurs with any fabric-connected storage, and is not
specific to the HP 3PAR StoreServ Storage system mentioned in this guide.
Target port limits and specifications 21