[Feature] Have kdump installed by default on ubuntu AKS worker nodes

reenakabra commented 2 years ago

Is your feature request related to a problem? Please describe. A clear and concise description of what the problem is. Ex. I'm always frustrated when [...]

For the cases where kernel modules are loaded on AKS worker node, kdump is required to collect the crash dump generated in case of failures/error. Configuring kdump requires a reboot. Also, considering the nature of nodes is ephemeral this needs to be done every time the node comes up.

Describe the solution you'd like A clear and concise description of what you want to happen.

Install kdump (linux-crashdump) on ubuntu AKS worker nodes along with the other packages that are installed by default.

Describe alternatives you've considered A clear and concise description of any alternative solutions or features you've considered.

Alternative is to deploy daemonset on cluster that will use nsenter to install linux-crashdump and reboot the system.

Additional context Add any other context or screenshots about the feature request here.

Tried accessing aks worker node using kubectl debug node/ command as mentioned on https://docs.microsoft.com/en-us/azure/aks/node-access. But crash fails to run with below error.

root@aks-agentpool-41145517-vmss00000G:/# crash /usr/lib/debug/boot/vmlinux-5.4.0-1085-azure

crash 7.2.8 Copyright (C) 2002-2020 Red Hat, Inc. Copyright (C) 2004, 2005, 2006, 2010 IBM Corporation Copyright (C) 1999-2006 Hewlett-Packard Co Copyright (C) 2005, 2006, 2011, 2012 Fujitsu Limited Copyright (C) 2006, 2007 VA Linux Systems Japan K.K. Copyright (C) 2005, 2011 NEC Corporation Copyright (C) 1999, 2002, 2007 Silicon Graphics, Inc. Copyright (C) 1999, 2000, 2001, 2002 Mission Critical Linux, Inc. This program is free software, covered by the GNU General Public License, and you are welcome to change it and/or distribute copies of it under certain conditions. Enter "help copying" to see the conditions. This program has absolutely no warranty. Enter "help warranty" for details.

crash: /dev/mem: Operation not permitted

Do we need additional securityContext for the container?

securityContext: privileged: true runAsUser: 0

reenakabra commented 2 years ago

@phealy Just wondering if you can update or share your thoughts if kdump should be installed by default on AKS worker node.

alexxiongxiong commented 1 year ago

@phealy Just wondering if you can update or share your thoughts if kdump should be installed by default on AKS worker node.

kdump isn't enabled by default in AKS.