32.5. Using sadump on Fujitsu PRIMEQUEST systems

On Fujitsu PRIMEQUEST systems, you can also enable the stand-alone dump (sadump) functionality provided by the hardware. This utility operates by combining kdump, which is a standard part of Red Hat Enterprise Linux, and the additional sadump BIOS-based function provided by Fujitsu.

Note

For the purpose of ensuring a dump is captured in the event of an unexpected reboot, Fujitsu recommend that sadump is always enabled on PRIMEQUEST hardware.
The sadump utility is usually invoked when a kdump cannot be processed because Red Hat Enterprise Linux has became unresponsive. These conditions can include:
  • Red Hat Enterprise Linux panic or hang before kdump starts
  • An error while kdump is working

How to use sadump

To use sadump, complete the following steps:
  1. Install the following packages according to the kernel version in use:
    # yum install kernel-debuginfo kernel-debuginfo-common
  2. Configure UEFI for sadump
    For more details, see the FUJITSU Server PRIMEQUEST 2000 Series Installation Manual.
  3. Configure Red Hat Enterprise Linux for sadump
  4. Start sadump
    For more details, see the FUJITSU Server PRIMEQUEST 2000 Series Installation Manual.
  5. Check the memory dump

32.5.1. Configure Red Hat Enterprise Linux for sadump

  1. Ensure that kdump starts as expected for sadump:
    1. Configure Red Hat Enterprise Linux to not reboot after a kernel panic:
      By default, Red Hat Enterprise Linux reboots automatically after a kernel panic, which prevents sadump to start. To avoid this behavior, configure the /etc/sysctl.conf file as follows:
      kernel.panic=0
    2. Configure Red Hat Enterprise Linux to start kdump by Nonmaskable Interrupt (NMI):
      In the procedure of starting sadump, starting kdump by NMI is needed at first.
      Configure /etc/sysctl.conf as follows:
      kernel.unknown_nmi_panic=1
  2. Ensure that kdump behaves correctly for sadump:
    1. Configure Red Hat Enterprise Linux to stop after kdump:
      By default, Red Hat Enterprise Linux reboots automatically when kdump fails, which prevents sadump to start. To avoid this behavior, configure the /etc/kdump.conf file as follows:
      default halt
      or
      default shell
    2. Configure Red Hat Enterprise Linux to start sadump:
      Configure /etc/kdump.conf to not block the System Management Interrupt (SMI) and thus to enable sadump to start:
      blacklist kvm-intel