How to Modify a Crash Dump Configuration

1. Become superuser or assume an equivalent role.

   Roles contain authorizations and privileged commands. For more information about roles, see Configuring RBAC (Task Map) in System Administration Guide: Security Services.

2. Identify the current crash dump configuration.

   # dumpadm Dump content: kernel pages Dump device: /dev/dsk/c0t3d0s1 (swap) Savecore directory: /var/crash/pluto Savecore enabled: yes Save commpressed: on

   This output identifies the default dump configuration for a system running the Oracle Solaris 10 release.

3. Modify the crash dump configuration.

   # /usr/sbin/dumpadm [-nuy] [-c content-type] [-d dump-device] [-m mink | minm | min%] [-s savecore-dir] [-r root-dir] [-z on | off]

   -c content

   Specifies the type of data to dump. Use kernel to dump of all kernel memory, all to dump all of memory, or curproc, to dump kernel memory and the memory pages of the process whose thread was executing when the crash occurred. The default dump content is kernel memory.

   -d dump-device

   Specifies the device that stores dump data temporarily as the system crashes. The primary swap device is the default dump device.

   -m nnnk | nnnm | nnn%

   Specifies the minimum free disk space for saving crash dump files by creating a minfree file in the current savecore directory. This parameter can be specified in Kbytes (nnnk), Mbytes (nnnm) or file system size percentage (nnn%). The savecore command consults this file prior to writing the crash dump files. If writing the crash dump files, based on their size, would decrease the amount of free space below the minfree threshold, the dump files are not written and an error message is logged. For information on recovering from this scenario, see How to Recover From a Full Crash Dump Directory (Optional).

   -n

   Specifies that savecore should not be run when the system reboots. This dump configuration is not recommended. If system crash information is written to the swap device, and savecore is not enabled, the crash dump information is overwritten when the system begins to swap.

   -s

   Specifies an alternate directory for storing crash dump files. The default directory is /var/crash/hostname where hostname is the output of the uname -n command.

   -u

   Forcibly updates the kernel dump configuration based on the contents of the /etc/dumpadm.conf file.

   -y

   Modifies the dump configuration to automatically execute the savecore command upon reboot, which is the default for this dump setting.

   -z on | off

   Modifies the dump configuration to control the operation of the savecore command upon reboot. The on setting enables the saving of core file in a compressed format. The off setting automatically uncompresses the crash dump file. Because crash dump files can be extremely large and therefore require less file system space if they are saved in a compressed forma, the default is on.

Example 17–1 Modifying a Crash Dump Configuration

In this example, all of memory is dumped to the dedicated dump device, /dev/dsk/c0t1d0s1, and the minimum free space that must be available after the crash dump files are saved is 10% of the file system space.

# dumpadm
      Dump content: kernel pages
       Dump device: /dev/dsk/c0t3d0s1 (swap)
Savecore directory: /var/crash/pluto
  Savecore enabled: yes
   Save compressed: on
 # dumpadm -c all -d /dev/dsk/c0t1d0s1 -m 10%
      Dump content: all pages
       Dump device: /dev/dsk/c0t1d0s1 (dedicated)
Savecore directory: /var/crash/pluto (minfree = 77071KB)
  Savecore enabled: yes
    Save compressed: on