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

olrad command provides an option to override the flag and proceed with the removal of I/O
components. For example, if an IP address is configured on a networking port, it is considered a
DATA CRITICAL usage.
CRA_SYSTEM_CRITICAL - Indicates critical resources are in use. If these resources are taken
offline, the system could crash. Swap and boot configurations are examples. With system critical
resources in use, the corresponding I/O component should not be allowed to be taken offline.
CRA_FAILURE
- Indicates that internal errors occurred during the analysis.
The Critical Resource Analysis may take anywhere between less than a minute to several minutes to
complete, depending on system configurations. In most of the typical system configurations, the CRA
will complete in less than a minute and in large configurations with large number of interface cards,
and storage devices with multi-paths, the CRA may take several minutes to complete.
Each subsystem CRA module provides a detailed log of resource usage for its corresponding
subsystem. The infrastructure CRA module combines these logs and provides a system wide usage
report for I/O components.
The subsystem CRA log format has a Detailed Report section. The information contained in the
Detailed Report provides a system administrator with detailed information on resource usage in a
subsystem.
The CRA log can be found on the system at the following location /var/adm/cra.log .
This whitepaper provides insight into the typical CRA scenarios. The scenarios are discussed at the
following levels:
• Various possible system configuration scenarios.
• Operations that may be performed on the machine, which, if appropriate precaution is not
taken, can sometimes lead to system instability or data loss issues.
• The CRA resource usage report generated for that configuration and operation to be
performed
• If the operation is blocked by the CRA and if it is necessary to go ahead with the operation,
a recommendation to safely carry out the intended operation.
Mass Storage CRA Scenarios
Mass storage CRA is a subsystem invoked by the CRA infrastructure to perform resource analysis on
mass storage components on the system. Mass storage components are those that belong to class of
devices, such as FC (Fiber Channel), SCSI (Small Computer System Interface), SAS (Serial Attached
SCSI), etc.
Boot Path Configuration Scenarios
Scenario 1
System Configuration: HP-UX OS running from a boot disk with a single lunpath under an HBA.
Operation Performed: # olrad –C | -r | -d <slot id>
Or
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