HP 3PAR X9000 File Serving Software (IBRIX) Implementation Guide (QL226-96987, June 2013)

Installing the QLogic HBA
Install the QLogic host bus adapter(s) in the host server based on the documentation provided with
the HBAs and host server.
Modifying the /etc/modprobe.conf File and Building the Ramdisk
1. As shown below, modify the options qla2xxx line to include qlport_down_retry=1
if you are running a version of InForm OS earlier than 3.1.1. If you are running InForm OS
3.1.1 or later, enter qlport_down_retry=10. This HBA options setting is required for
desired multipath to act quickly for failover/failback operation.
The modified output of /etc/modprobe.conf represents as an example:
# cat /etc/modprobe.conf
alias eth0 bnx2
alias eth1 bnx2
alias scsi_hostadapter cciss
alias scsi_hostadapter1 qla2xxx
options qla2xxx qlport_down_retry=1
NOTE: The kernel loads the SCSI drivers from ramdisk in the order in which they were
defined in the /etc/modprobe.conf file and assigns the SCSI device entries (sda, sdb)
in ascending order starting with the first entry, for each entry where a SCSI device exists. If
the host has a SCSI boot disk, it must obtain device entry sda as those entries are hard coded
in the bootloaders. Therefore, the scsi_hostadapter entry that supports the boot disk must
appear first in the /etc/modprobe.conf file.
If a fan-out configuration is used, where an HP 3PAR StoreServ Storage port is connected to
many hosts through the fabric, it is possible that the target port will run out of I/O buffers and
will result in the target port issuing a QUEUE FULL SCSI status message to any new incoming
I/O requests from any host on that port. To prevent this event, you can throttle the host Port
Queue depth and LUN Queue depth. By default, the QLogic driver sets Port Queue depth
(Execution Throttle) to FFFF (65535) (overriding the default BIOS execution value of 32) and
sets the LUN Queue Depth to 32 (default). You can throttle the LUN Queue depth value to a
lower value using the ql2xmaxqdepth parameter. QLogic does not offer any driver setting
to change the Port Queue depth or Execution Throttle. Change the default values if any throttling
is required.
In the following example, the output shows the /etc/modprobe.conf when the
ql2xmaxqdepth parameter is set to 16.
# cat /etc/modprobe.conf
alias eth0 bnx2
alias eth1 bnx2
alias scsi_hostadapter cciss
alias scsi_hostadapter1 qla2xxx
options qla2xxx qlport_down_retry=1 ql2xmaxqdepth=16
REQUIRED
Storage administrators should carefully consider the number of hosts connected to an HP 3PAR
StoreServ Storage port and the number of LUN exports for calculating the throttling configuration
values. Performance degradation and SCSI timeout issues will result if the values are set too
low.
2. Rebuild the ramdisk image after the /etc/modprobe.conf file entries are modified. As the
mkinitrd command requires the initrd file, check the contents of the /etc/grub.conf
16 Connecting a StoreAll 9300 with Fibre Channel