Chapter 2. Installing and Configuring kdump

2.1. Installing kdump

In many cases, the kdump service is installed and activated by default on new Red Hat Enterprise Linux 7 installations. The Anaconda installer provides a screen for kdump configuration when performing an interactive installation using the graphical or text interface. The installer screen is titled Kdump and is available from the main Installation Summary screen, and only allows limited configuration - you can only select whether kdump will be enabled and how much memory will be reserved. Information about memory requirements for kdump is available in Section B.1, “Memory Requirements for kdump”. The Kdump configuration screen in the installer is documented in the Red Hat Enterprise Linux 7 Installation Guide.

Note

In previous releases of Red Hat Enterprise Linux, kdump configuration was available in the Firstboot utility which was automatically executed after the installation finished and the system rebooted for the first time. Starting with Red Hat Enterprise Linux 7.1, kdump configuration has been moved into the installer.
Some installation options, such as custom Kickstart installations, may not install or enable kdump by default. If this is the case on your system, and you want to install kdump additionally, execute the following command as root at a shell prompt:
# yum install kexec-tools
This will install kdump and all other necessary packages, assuming your system has an active subscription or a custom repository containing the kexec-tools package for your system's architecture.

Note

If you do not know whether kdump is installed on your system, you can check using rpm:
$ rpm -q kexec-tools
Additionally, a graphical configuration tool is available, but not installed by default if you use the command described above. To install this utility, which is described in Section 2.3, “Configuring kdump in the Graphical User Interface”, use the following command as root:
# yum install system-config-kdump
For more information on how to install new packages in Red Hat Enterprise Linux 7 using the Yum package manager, see the Red Hat Enterprise Linux 7 System Administrator's Guide.

Important

A limitation in the current implementation of the Intel IOMMU driver can occasionally prevent the kdump service from capturing the core dump image. To use kdump on Intel architectures reliably, it is advised that the IOMMU support is disabled.