Need Help, How can get the full install log

[Erik Skultety]

On Wed, Sep 21, 2022 at 01:53:20PM +0800, Lucas Liu wrote:
> Gratings:
> 
> Recently, I got an error while installing a guest, the error message is
> this,:
> [image: image.png]
> 
> Is there a method to get the full log? I have tried to use virt-install
> --console, or attach <log
> file="/var/log/libvirt/qemu/guestname-serial0.log" append="off"/>  to get
> the full log, but they didn't work.

They didn't work because the serial console isn't enabled on the kernel cmdline
by default, so you'll need to pass "--extra-args 'console=ttyS0,112500'" when
installing a guest with virt-install. Note that once installed, you'll need to
tweak /etc/default/grub to enable serial console permanently for that VM,
otherwise you'll have a character device but no serial output would be relayed
there.

I also recommend to use "--autoconsole text" instead of "--console xyz" for
your purpose as "--console" is a generic character device which you need to (at
least somehow) configure, while "--autoconsole" is syntactic sugar that does
the magic for you.

PS: in case you'd like to install guests from pre-built templates with
virt-builder from the guestfs-tools package then these have been built so that
/etc/default/grub was already tweaked to enable serial output, hence
"--extra-args" could be completely omitted in that case and you'd only use
"--autoconsole text" --> you can give it a try to observe the difference :)

Regards,
Erik