Technical data

Table 8 Configuration limits for Se cure Path 3.0F SP3 Active-Active disk arrays
Parameter
Minimum
Maximum qualified
Maximum supported
Adapter support
1
4
Platform limit
Storage arrays per host
1
4
Platform limit
LUNs per storage array per host
1
Array limit Array limit
Paths per LUNs
1
32
N/A
Avoiding problem situations
The following problems may arise during Secure Path operations:
• The status of a path is updated only when I/O occurs on that path or when proactive path
monitoring is enabled.
• Only Fibre Channel connectivity is s upported.
• When all paths to an end LUN fail in the case of I/O to non-LVM devices with the HFS file system,
or asynchronous I/O to non-LVM devices, I/O to the LUN waits until connectivity through these
paths are restored. I/O starts only if the original path (the path on which I/O was started)
is restored.
• Secure Path does not recognize newly added paths or devices that are in use before running the
autopath discover command.
• Devices are not discovered automatically on installation and after reboot, if autopath
discover is set to off.
• Discovery of new paths or LUN s occurs only if ioscan and insf -e are run before running the
autopath discover command.
• If ioscan and insf -e are not run before running the autopath discover command, and
if changes are made in the SAN, autopath discover may take a long time to complete
because of attempted retries by the lower-level layers on the device paths.
• TheSecurePathcommandlineutility(autopath) does not support wildcard characters. For
example, you cannot use the question mark (?) with a command to invoke the help command.
• If HPswsp is marked for removal using swremove, a nd if the remove process is aborted, the
load balancing policy setting is reset to NLB (the default).
• InaLUNcollision,thenewLUNisdiscoveredthroughpathsusedbytheoldLUN,providedthe
old LUN is not mou nted or open. If the old LUN is mounted or open, the paths to the old LUN are
marked as failed because the LUN is unpresented. To recover the old LUN, assign the same SCSI
LUN ID to the old LUN. To access the new LUN, present it at a different SCSI LUN I D, or unmount
or close the old LUN and run the autopath discover command.
NOTE:
• Supports Infinite Retry for VxFS file system only.
• If a device configured under the HFS file system encounters an All Paths Fail condition, I/O
restartsonlyifthepathonwhichitwasstartedisactive.
• If the file system changes from VxFS to HFS, Secure Path 3.0F SP3 for Active-Active disk arrays does
notautomaticallysetthetimeoutvalueforaLUNasInfinite Retry.
• Use autopath delete command before un-presenting the LUN from the host server. This will remo ve
the existing WWN reference and avoid LUN collisions. This command also n eeds to be included in
any scripts/applications which add/remove LUNs under Secure Path control.
• Theownershipofthevirtualdevicespecialfi les created by Secure Path under /hpap/dsk or
/hpap/rdsk may change on reboot. Applications are required to reset the ownership and permission
on reboot.
HPStorageWorksSecurePath3.0FServicePack3forHP-UX11iv1.0and11iv2.0
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