System Dump Facility

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Your system generates a system dump when a severe error occurs. System dumps can also be user-initiated by users with root user authority. A system dump creates a picture of your system's memory contents. System administrators and programmers can generate a dump and analyze its contents when debugging new applications.

System dumps can be assisted by firmware. Different from traditional system dumps that are generated before the partition is reinitialized, firmware-assisted system dumps take place when the partition is restarting. Firmware-assisted system dumps can be one of these types:
Selective memory dump
Selective memory dumps are triggered by or use AIX® instances that must be dumped.
Full memory dump
The whole partition memory is dumped without any interaction with an AIX instance that is failing.
By default, the system generates a traditional system dump. After you explicitly enable a firmware-assisted system dump, it becomes the preferred system dump. However, if the configuration of the firmware-assisted system dump fails, the system generates a traditional system dump. A firmware-assisted system dump takes place under the following conditions:
  • The platform supports firmware-assisted system dumps. AIX retrieves the property of firmware-assisted system dumps in the device tree to get the information.
  • The memory size at system startup is equal to or greater than 1.5GB.
  • You have not configured a traditional system dump.

A firmware-assisted dump cannot copy dump tables. Because the data is written on the next restart of the system, the dump tables, which are used to refer to the data, cannot be preserved.

RAS infrastructure components can be system-dump aware, allowing granular control of the amount of data that is dumped in a system dump by infrastructure components. Components that are system-dump aware can be excluded from a system dump to reduce the dump size. You can use the dumpctrl command to obtain information about which infrastructure components are registered for a system dump.

Use the ras_register kernel service to make an infrastructure component dump-aware. Use the RASCD_SET_SDMP_ON command that is passed to the ras_control kernel service to make an infrastructure component system-dump aware. See Callback Commands for System Dumps.

If your system stops with an 888 number flashing in the operator panel display, the system has generated a dump and saved it to a dump device (the condition only occurs with traditional system dumps).

Some of the error log and dump commands are delivered in an optionally installable package called bos.sysmgt.serv_aid. System dump commands included in the bos.sysmgt.serv_aid include the sysdumpstart command. See the Software Service Aids Package for more information.

To generate a system dump see the following topics:

EMC PowerPath support for traditional and firmware assisted dump

To complete a traditional assisted dump or a firmware assisted dump, you must have an installation of EMC PowerPath Version 5.7, or later, or you must have an installation of EMC PowerPath Version 5.5.0.2, or earlier. For example, if you have and installation of EMC PowerPath Version 5.6, you cannot complete a traditional assisted dump or a firmware assisted dump.