The dumpadm and savecore utilities configure and manage the creation of a crash dump as follows:
During system startup, the dumpadm command is invoked by the svc:/system/dumpadm:default service to configure crash dump parameters. It initializes the dump device and the dump content through the /dev/dump interface.
After the dump configuration is complete, the savecore script looks for the location of the crash dump file directory. Then, savecore is invoked to check for crash dumps and check the content of the minfree file in the crash dump directory. System crash dump files generated by the savecore command are saved by default.
Dump data is stored in a compressed format on the dump device. Kernel crash dump images can be as large as 4 Gbytes or more. Compressing the data means faster dumping and less disk space required for the dump device.
When a dedicated dump device, not the swap area, is part of the dump configuration, the saving of crash dump files is run in the background, A system that is booting does not wait for the savecore command to complete before going to the next step. On large memory systems, the system can be available before savecore completes.
The savecore –L command enables an administrator to get a crash dump of a currently running the Oracle Solaris OS. This command is intended for troubleshooting a running system by taking a snapshot of memory during some bad state, such as a transient performance problem or service outage. If the system is up and you can still run some commands, you can execute the savecore –L command to save a snapshot of the system to the dump device and then immediately write out the crash dump files to your savecore directory. Because the system is still running, you can use the savecore –L command only if you have configured a dedicated dump device.
For more information, see Modifying the Configuration for Crash Dumps, the dumpadm (1M) , and the savecore (1M) man pages.