Adjusting kdump settings and GRUB kernel parameters

This guide describes the solutions to the specific issues encountered during installations and provides detailed information for each case.

Change KERNEL_MODULES in kdump config from dep to most

To ensure including more kernel modules set the following setting, which lead to increasing the size of the initramfs.

sed -i 's/KDUMP_MODULES=dep/KDUMP_MODULES=most/' /etc/kernel/postinst.d/kdump-tools
rm /var/lib/kdump/initrd*
kdump-config reload

Prevent autosuspend on USB devices blocking the kdump kernel load

By default, the kernel can suspend extensible Host Controller Interface (xHCI). As a result, during boot or a crash, the system waits for a response from the controller - but the controller does not “respond” because it’s already in a suspended state, and the process hangs. After blacklisting the whole module in the kdump kernel modules, the node crash was completed successfully.

There are two ways to disable autosuspend of the controller:

Blacklist the module in the kdump configuration:

/usr/lib/storpool/patchkdumptools xhci_pci
systemctl restart kdump-tools
kdump-config show | grep xhci_pci
 /sbin/kexec -p --command-line="BOOT_IMAGE=/vmlinuz-6.8.0-85-generic
 root=UUID=bfb3159e-0f94-4de6-93de-f5e2b358e503 ro iommu=pt intel_iommu=on
 … modprobe.blacklist=mlx5_core modprobe.blacklist=xhci_pci xhci_pci.blacklist=yes"
 --initrd=/var/lib/kdump/initrd.img /var/lib/kdump/vmlinuz

Disable the autosuspend as a grub parameter by including in the GRUB_CMDLINE_LINUX:
usbcore.autosuspend=-1

For detailed information how to connect to a Server’s Serial Console using IPMI and Serial-Over-LAN (SOL), please check Server Serial-Over-LAN (SOL) Configuration and Access.