Interface Card Critical Resource Analysis(CRA) Whitepaper for HP-UX 11i v3

Scenario 17
System Configuration:
Disk has been configured as a mirror copy of a logical volume (could be either
LVM or VxVM volume) with file system mounted on it. The mirror disk has only one lunpath, where the
lunpath originates from a different I/O card as compared to the primary mirror copy.
Operation Performed:
# olrad –C | -r | -d <slot id>
Or
# scsimgr disable –H <mirror disk lunpath>
Criticality reported by CRA:
CRA_WARNING or CRA_DATA_CRITICAL
Explanation and user action required:
The olrad (1M) command with –C option reports the resource usage and its criticality.
The above operations with scsimgr and olrad (1M) with –r or –d options will display a WARNING
indicating that the operation will make the lunpath to mirror disk unavailable.
However, if there is any process that is keeping the mirror disk open, then the above operations will
return the CRA_DATA_CRITICAL error.
If the user chooses to proceed with the requested operation or override the error (in case of
CRA_DATA_CRITICAL), the user must remember that the system is then vulnerable and a failure
might occur while reading data from the primary mirror copy. This could potentially bring down the
system.
If any of these operations must be performed for system administration purposes, then an alternative
path must be configured using the same or a different card (in case of the scsimgr operation) or
through an alternative healthy card (in case of the olrad operation) before performing the above
operations.
Scenario 18
System Configuration:
Disk has been configured as a mirror copy of a logical volume (could be either
LVM or VxVM volume) with file system mounted on it. This mirror disk has multiple lunpaths which
originate from different ports of the same card (for example, AB379B dual-ported 4GB FC card).
Operation Performed:
# olrad –C | -r | -d <slot id>
Or
# scsimgr disable –H <mirror disk lunpath>
Criticality reported by CRA:
CRA_WARNING or CRA_DATA_CRITICAL
Explanation and user action required:
The olrad(1M) command with –C option reports the resource usage and its criticality.
The above operation with scsimgr will not have any user impact as long as there is at least one
another lunpath available to the mirror disk. However, if the last lunpath is disabled, then this
operation will report a WARNING.
Though there are multiple paths, the above operations with olrad(1M) with –r or –d options will
display a WARNING indicating that the operation will make all lunpaths to the mirror disk
unavailable as they are all from the same card.
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