Kdump is a reliable tool used in Linux to capture kernel crash dumps (vmcores) when the system encounters a kernel panic. Here's a step-by-step guide to install and configure Kdump on a CentOS-based system:

Step 1: Install Kdump

1. Update the package repository:

   bash

• sudo yum update

• Install the Kdump package:

  bash

2. sudo yum install kexec-tools crash

Step 2: Configure Kdump

1. Open the Kdump configuration file in a text editor:

   bash

• sudo nano /etc/kdump.conf

• Configure the destination for the vmcore. By default, Kdump saves the dump in /var/crash. You can adjust this location if needed.

  Example:

  bash

2. path /var/crash

3. Save and close the file.

Step 3: Configure Grub

1. Open the Grub configuration file:

   bash

• sudo nano /etc/default/grub

• Add or modify the crashkernel option. This determines how much memory to reserve for Kdump. Set an appropriate value based on your system's requirements.

  Example:

  makefile

Make sure to regenerate the Grub configuration file:

2. sudo grub2-mkconfig -o /boot/grub2/grub.cfg

Step 4: Enable and Start Kdump Service

1. Enable the Kdump service:

   bash

• sudo systemctl enable kdump

• Start the Kdump service:

  bash
• sudo systemctl start kdump

• Verify that the Kdump service is running:

  bash

3. sudo systemctl status kdump

Step 5: Test Kdump

1. Trigger a Kernel Panic:

   You can do this by running:

   bash