[PATCH] Documentation: step by step guide on confiuring kdump in live images
This is a short documentation on how to setup kdump on live images. All steps
was tested on Fedora 25 Alpha LiveCD and successfully saved vmcore captured
by kdump to a USB stick.
Signed-off-by: Tong Li <tonli(a)redhat.com>
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+Kdump now can work on Live images, but some manual configurations are needed.
+Here is the step by step guide. Please use root privilege.
+
+0. (if you are using old versions of kexec-tools)
+ Apeend "root" to KDUMP_COMMANDLINE_REMOVE variable in /etc/sysconfig/kdump
+
+Live images are booted with a kernel parameter which looks like
+"root=live:CDLABEL=Fedora-WS-Live-25_A-2". This argument can't be
recognized
+by dracut during kdump process and will cause failure of kdump. So we need
+to make sure 'root' parameter is removed during kdump process.
+
+1. Change dump target in /etc/kdump.conf
+
+When kdump is triggered in a Live environment, the default target /var/crash
+will not be mounted and unable to be used to save vmcore. You can modify it to
+make kdump save the captured dump file on an external disk or send it with ssh
+throught network.
+
+2. Run 'kdumpctl start' to build kdump initramfs and start kdump.
+
+Here is all configurations you need to tweak manually. If you want to confirm
+whether kdump is working or not, you can use sys-trigger interface by running:
+
+ $ echo 1 > /proc/sys/kernel/sysrq
+ $ echo c > /proc/sysrq-trigger