Re: [Qemu-devel] Re: How to get target system display with qemu -nographic option?

[Atoosah <atoosaah@gmail.com>]

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Yay! I've almost got it. I'd appreciate a bit more help for the last few
steps.

Thank you David for pointing out the command options wouldn't be recognized.
Now, I see how it wouldn't make sense to pass in commands to a bootable
image. I had previously added the same console parameters to grub, but the
kernel was not recognizing it.

Vikram, thank you telling me about the -B option. That was the key :-) My
kernel is not that old, 2.6.11, and so needed that option. Now I get the
boot up messaged on my terminal!

-- But, after bootup messages are done, I do not see the login screen. After
the last bootup messages are done, shouldn't the login screen magically
appear on the terminal? I don't see anyting after the last bootup message
of  "Starting HAL daemon: [  OK ]". Why would that be?

-- Also, I'm easily able to switch to Qemu's Command window with Ctrl-a c,
but cannot switch back to console. Shouldn't I be able to?

Below I've listed the changes (on a 2.6.11 Fedora Core guest) I've made in
case someone needs to refer to it:

A) modified grub.conf as follows:
default=0
timout=10
serial --unit=0 --speed=9600
terminal serial console
title something
         root (hd0,0)
         kernel some_stuff -B console=ttyS0
         initrd something

B) In /etc/inittab mgetty was giving me respawning error so I removed the
below line. It seems that mgetty was not being recognized.
#T0:2345:respawn:/sbin/mgetty dev=ttyS0 b 9600 ...

Vikram, have you tried mingetty? I don't have getty available.

C) Running qemu as follows:
$ qemu  -hda myboot.img -m 512 -nographic

-----------------------------------------------------------------------
Note: my last last boot message are:
Checking filesystems
Checking all file systems.
...
[  OK  ]
Remounting root filesystem in read-write mode:  [  OK  ]
Mounting local filesystems:  [  OK  ]
Enabling local filesystem quotas:  [  OK  ]
Enabling swap space:  [  OK  ]
INIT: Entering runlevel: 3
Entering non-interactive startup
Checking for new hardware [  OK  ]
Starting pcmcia:  [  OK  ]
Starting system logger: [  OK  ]
...
Starting system message bus: [  OK  ]
Starting HAL daemon: [  OK  ]

-----------------------------------------------------------------------

Thank you.



> Hi,
>
> There are two components to making output appear on the serial port.
>
> 1. Getting GRUB to output (the menu etc.) to the serial port. You can do
> this via the following global directive
>          serial --unit=0 --speed=9600
>          terminal serial
> Add this as a "global" entry to grub.conf  i.e. at the same level as your
> "default" and "timeout" directives (i.e. outside the title block)
>
> 2. Getting the Linux kernel to output console to the serial port (once it
> takes over from GRUB). I don't
>    have experience doing console redirection on Linux but on Opensolaris we
> do it via a property specified via
>    a -B option specified  on the "kernel" line.
>
> Atoosah wrote:
> > title Fedora ....
> > console=ttyS0   ....
>
> This is unlikely to work - the "console" token is interpreted by GRUB as a
> command and there is no "console" command in legacy GRUB.
>
> Vikram
>
> ----- Original Message ----
>
> Ah, you're going well outside my area of familiarity -- I've never set
> up a console terminal over a serial line physically nor virtually.
>
> However, I notice you're using the "-append" line -- I made that mistake
> as well, but learned that you can only use "-append" if you're also
> using "-kernel" and "-initrd".  Basically, you can wholly specify the
> kernel in the qemu command line, or you need to go with the kernel
> defined by GRUB, but you can't selectively override grub using the
> command line.
>
> Other than that, I'm not sure how to help.  Good luck!
>
> -david
>
>

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