Re: Xen Paravirt Operations Domain 0 Serial Console Problem

["Mr. Teo En Ming (Zhang Enming)" <enming.teo@asiasoftsea.net>]

Hi,

The main purpose of doing this is that I want to boot using serial 
console and free up the VGA card for direct access by the Windows HVM 
guest using VT-d IOMMU. But it seems I cannot get serial console working.

Please advise.

Thank you.

-- 
Mr. Teo En Ming (Zhang Enming) Dip(Mechatronics Engineering) BEng(Hons)(Mechanical Engineering)
Technical Support Engineer
Information Technology Department
Asiasoft Online Pte Ltd
Tampines Central 1 #04-01 Tampines Plaza
Singapore 529541
Republic of Singapore
Mobile: +65-9648-9798
MSN: teoenming@hotmail.com
Alma Maters: Singapore Polytechnic, National University of Singapore



On 08/25/2009 12:17 AM, Mr. Teo En Ming (Zhang Enming) wrote:
> Hi All,
>
> I have tried to configure serial console for Xen hypervisor, dom 0 
> kernel and Linux login but it does not seem to be working.
>
> Here is my grub configuration for serial console:
>
> title Fedora (2.6.31-rc6-enming.teo) Serial Console
>         root (hd0,0)
>         kernel /xen.gz iommu=1 com1=115200,8n1 console=com1
>         module /vmlinuz-2.6.31-rc6-enming.teo ro 
> root=/dev/mapper/vg_fedora11_host-lv_root selinux=0 console=ttyS0,115200
>         module /initrd-2.6.31-rc6-enming.teo.img
>
> Is the above configuration correct? On my Intel Desktop Board DQ45CB, 
> I have a COM1 header on the PCB and I have connected an external 
> serial port to this header and also enabled COM1 in the BIOS.
>
> After selecting the above entry in GRUB still on VGA, a cursor at the 
> top left corner of the monitor shows up, which means Xen and Dom 0 
> kernel are booting up on the serial console and not on VGA.
>
> However, after some time, a login prompt finally displays on my VGA 
> monitor! Isn't it NOT supposed to show up on VGA and should show up in 
> serial console instead?
>
> All the while I get nothing displayed on the Windows laptop connected 
> to the serial console of the Xen machine. I am using Windows Hyper 
> Terminal with a null modem cable and a USB-to-Serial converter cable.
>
> After seeing nothing on Hyper Terminal, I go to the VGA console (tty1) 
> and keyboard and pressed CTRL-ALT-DEL to reboot the Xen machine.
>
> Then finally I see this screenshot:
>
> http://2.bp.blogspot.com/_zzjv8MCM2sk/SpK6D_eSIfI/AAAAAAAAATs/NdSPpfddTvQ/s1600-h/xen+serial+console.JPG 
>
>
> After that, I select rebooting using serial console but I still see 
> nothing on Hyper Terminal.
>
> May I know what's happening and what's wrong with serial console?
>
> Thank you.
>