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and suspend the I/O modules in the error path. When this phase is completed, it is assumed that
drivers have suspended all activities for the devices in the error path. On HP Superdome 2 platform
system, during this phase the Health Checker Daemon is invoked to log and clear the errors.
Release Phase: During this phase, the suspended I/O path is restored. It involves resuming the driver.
If any I/O cards were left in a suspended state, the card will be replaced via a PCI OLR action.
For more information about PCI OLR, see Interface Card OL* Support Guide, posted at the following
location:
http://www.hp.com/go/hpux-networking-docs under
HP-UX 11i v3 Networking Software category.
The following diagram depicts various phases of core PSM.
Figure 4: PCI Error Recovery Phases
Diagnostics decodes the error logs and saves the error information in /var/opt/resmon/log/event.log
file.
Note: Only the PCI bus parity errors are handled by the error recovery feature. Device errors are not
handled by this feature.
To summarize, when an error occurs on a PCI bus containing an I/O card, events occur in the
following order:
 The I/O drivers are suspended
 The PCI bus is isolated from further I/O
 The error is logged and cleared
 The bus is reset
 The I/O drivers are resumed