[CentOS-virt] What is the purpose setting console=hvc0 in the dom0 grub config?
jerryubi at gmail.com
Wed May 17 15:37:13 UTC 2017
On Wed, May 17, 2017 at 8:25 AM, Konrad Rzeszutek Wilk <
konrad.wilk at oracle.com> wrote:
> > This is what's defined in /etc/default/grub following the install of the
> > Xen:
> > GRUB_CMDLINE_XEN_DEFAULT="dom0_mem=1024M,max:1024M cpuinfo
> > console=com1,tty loglvl=all guest_loglvl=all"
> > GRUB_CMDLINE_LINUX_XEN_REPLACE_DEFAULT="console=hvc0 earlyprintk=xen
> > nomodeset"
> > I didn't set these myself, this is what the xen package (or one of its
> > dependencies) is doing.
> > I'm still not clear on why hvc0 is needed, or why it's being set, but
> > I do know for sure is it was causing the boot messages to be suppressed.
> So the hvc0 is to use the PV console driver to pipe all the messages to
> the Xen one.
> And Xen is configured to use the serial console (com1=115200,8n1).
> Which means that all you Linux bootup info should be piped to that.
So how would I properly configure it to still write to tty without
disabling hvc0? Perhaps something like this?
Looks like I have some learning to do. Do you happen to know of a good
article explaining how console redirection works?
> But Linux is pretty quiet unless you add 'loglevel=10' or 'debug' on the
> Linux command line.
-------------- next part --------------
An HTML attachment was scrubbed...
More information about the CentOS-virt