HP-UX 11i v3 Native Multi-Pathing for Mass Storage (August 2012)

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Value of attribute load_bal_policy saved successfully
Value of attribute pref_tport saved successfully
Value of attribute preferred_path saved successfully
# scsimgr get_attr –D /dev/rdisk/disk17 –a load_bal_policy –a pref_tport
–a preferred_path
SCSI ATTRIBUTES FOR LUN : /dev/rdisk/disk17
name = load_bal_policy
current = round_robin
default = round_robin
saved =
name = pref_tport
current =
default =
saved =
name = preferred_path
current =
default =
saved =
To change the load_bal_policy attribute to least_cmd_load, run scsimgr as follows:
# scsimgr set_attr -D /dev/rdisk/disk17 -a load_bal_policy=least_cmd_load
Value of attribute load_bal_policy set successfully
# scsimgr get_attr -D /dev/rdisk/disk17
…
name = load_bal_policy
current = least_cmd_load
default = round_robin
saved
…
Pass-through LUN load balancing
The pass-through device driver (
esctl) only supports the path_lockdown multi-pathing policy. By
default, the SCSI stack internally selects the path on which to send I/O operations and sets the LUN
lpt_lockdown attribute to the hardware path of the locked down path. Run scsimgr to see the
lpt_lockdown attribute value:
# scsimgr get_attr -D /dev/pt/pt2 –a lpt_lockdown
…
name = lpt_lockdown
current = 0/4/1/0.0x500508b3009097f9.0x0
saved =
This shows that for device /dev/pt/pt2, the OS internally selected the lunpath of hardware path
0/4/1/0.0x500508b3009097f9.0x0.
To change the lunpath, run scsimgr as follows. The device must be in the UNOPEN state before
executing the command.
# scsimgr save_attr –D /dev/pt/pt2 –a lpt_to_lockdown=0/4/1/0/0.0x500508b3009097f1.0x0
To display the attribute value, enter the following command:
# scsimgr get_attr –D /dev/pt/pt2 –a lpt_to_lockdown
.
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