CHAPTER 5 Work after Operating System installation 5.5 Setup of dump environment (Linux)

5.5.1How to use sadump (Linux)

This section explains steps for sadump. Sadump allows you to store memory dump under the situation like below while kdump, the standard Red Hat Linux function does not allows this.

-OS panic or hang up before Kdump service starts

-Error while Kdump is working

1.Preparation

Install the following two packages corresponded the kernel version in use .

-kernel-debuginfo-common

-kernel-debuginfo

2.Configuring UEFI

Read “5.3 Setting of sadump” to configure UEFI for sadump. Note the following points.

-Set “RECYCLE” in Set up Manager to “<Enable>”. If it is not “<Enable>”, configuring dump devices is needed every time after taking a memory dump by sadump.

-Select “Create a dump device” in Dump device Manager, and set “Create mode” to “<Single>”.” <Multiple>” is not supported.

3.Configuring OS

Kdump need to be set up beforehand to use sadump. After configuring Kdump, the additional configuration is needed as follows.

-Configuration not to reboot after panic

Set kernel parameter “kernel.panic” to 0 (default is 0). If not set, system reboot automatically after panic and the chance to start sadump is missed. Configure /etc/sysctl.conf as follows.

kernel.panic=0

-Configuration to stop system after Kdump

In /etc/kdump.conf, set “default” to “halt” or “shell”. If not set, system reboot automatically when Kdump fails and the chance to start sadump is missed.

-Configuration to start sadump

Set “blacklist kvm-intel” in /etc/kdump.conf. If not set, SMI is blocked and sadump cannot start.

Example of /etc/kdump.conf

ext4 LABEL=/dump path /

core_collector cp --sparse=always extra_bins /bin/cp disk_timeout 60

default shell blacklist kvm-intel

-Configuration to start Kdump by NMI

As a procedure to start sadump, starting Kdump by NMI is needed at first. Configure /etc/sysctl.conf as follows.

kernel.unknown_nmi_panic=1

4.Start sadump and confirmation Start sadump as follows.

1)Send NMI to start Kdump

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