The Kdump feature provides a kernel crash information dumping mechanism in Oracle Linux. The kdump service saves the contents of the system’s memory for later analysis. Kdump includes a second kernel that resides in a reserved part of the system memory, so that Kdump can capture information about a stopped kernel.

Kdump uses the kexec system call to boot into the second kernel, called a capture kernel, without the need to reboot the system, and then captures the contents of the stopped kernel’s memory as a crash dump (vmcore) and saves it. The vmcore crash dump can help with finding the cause of the malfunction.

Enabling the Kdump feature is highly recommended because a crash dump might be the only information source that's available if a system failure occurs. Kdump is vital in many mission-critical environments.

Before enabling Kdump, ensure that the system meets all the memory requirements for using Kdump. To capture a kernel crash dump and save it for further analysis, reserve part of the system's memory permanently for that purpose. When you do so, that part of the system's memory is no longer available to the main kernel.

For information about configuring Kdump by using the Cockpit web console, see Oracle Linux: Using the Cockpit Web Console