Do you want to have a backup plan in case something goes wrong with your kernel? Well, my friend, I’ve got some good news for you. Introducing kdump, the ultimate party crasher for your Linux system!

Now, before we dive into how to configure this magical tool, let me explain what it does and why you need it in your life. Kdump is a feature that allows you to dump the contents of memory when a kernel panic occurs. This can be incredibly useful if you’re trying to debug an issue or recover from a system failure.

With kdump, you can also reserve some memory for this purpose. That means your critical processes won’t get interrupted during the dump process and your system will continue running smoothly. This is especially important on IBM POWER systems where we have large amounts of memory to work with.

So how do we configure kdump memory reservation? It’s actually pretty simple, my friend! First, you need to edit your grub configuration file (usually located at /etc/default/grub). Add the following line:

# Set the GRUB_CMDLINE_LINUX variable to add our desired configuration.
GRUB_CMDLINE_LINUX="mem=1024M kdump=on"

This will reserve 1GB of memory for kdump and enable it. You can adjust the value to fit your needs, but make sure you have enough memory left over for your critical processes!

Next, update grub with:

# This script updates the grub configuration to enable kdump and reserve 1GB of memory for it.
# It is important to have enough memory left for critical processes.

# First, we need to update the grub configuration.
sudo update-grub

And reboot your system. That’s it! Now when a kernel panic occurs, kdump will automatically dump the contents of memory and save them to disk. You can then analyze these logs to figure out what went wrong and fix any issues.

Kdump also has some cool features like crash dumps over SSH or NFS, which means you don’t have to physically access your system to recover from a failure. This is especially useful for remote systems or data centers where you can’t be on-site all the time.

No more worrying about critical processes getting interrupted during kernel panics. Just sit back and let kdump do its thing while you enjoy a cold one with your Linux buddies. Cheers to the ultimate party crasher for your system!

Until next time, keep it casual and stay curious!