Automatic Server Recovery (ASR)
The Automatic Server Recovery is implemented using
a "heartbeat" timer that continually counts down.
The driver frequently reloads the counter to pre-
vent it from counting down to zero. If the ASR
counts down to 0, it is assumed that the operating
system is locked up and the system automatically
attempts to reboot. Events which may contribute to
the operating system locking up include:
* A peripheral device (such as a PCI adapter) failing
in such a way that numerous spurious interrupts are
generated.
* A high priority software application consumes all
the available CPU cycles and does not allow the
operating system scheduler to run the ASR timer
reset process.
* A software or kernel application consumes all
available memory including the virtual memory space
(i.e. swap). This may cause the operating system
scheduler to cease functioning.
* A critical operating system component such as a
file system fails and causes the operating system
scheduler to cease functioning.
* Any other event besides an ASR timeout which causes
a Non-Maskable Interrupt (NMI) to be generated.
The ProLiant ASR feature is a hardware based timer. If a
true hardware failure occurs, the ProLiant Advanced Server
Management driver might not be called but the server will
be reset as if the power switch was pressed. The ProLiant
ROM code may log an event to the ProLiant Integrated Man-
agement Log (IML) when the server reboots.
The ProLiant Advanced Server Management driver is notified
via a Non-Maskable Interrupt (NMI). If possible, the
driver will attempt to perform the following actions:
* Displays a message on the console stating the prob-
lem
* Makes an entry in the ProLiant Integrated Manage-
ment Log (IML).
* Attempts to gracefully shutdown the operating sys-
tem to close the file systems.
There is not a guarantee that the operating system will
gracefully shutdown. This depends on the type (software or
hwardware) and severity of the error condition.
Message:
"ASR Detected by System ROM"
Description:
This message indicates that the ProLiant
Server ROM detected an ASR timeout. This
message is almost always present in the Pro-
Liant Integrated Management Log when an ASR
timeout occurs. If this is the ONLY "ASR"
message logged to the ProLiant Integrated
Management Log, this may be indicative of a
hardware failure (such as a non-correctable
ECC error on a memory DIMM). The ASR fea-
ture on a ProLiant server will hard reset
the server when the timeout expires with no
software intervention required.
Regards,
Matthijs
