Hi, all
Has anyone encountered a situation where the boot output stops after
switchroot is made? What happens in my instal is that xen''s serial
console output stops at the moment the WARNING message about tls is
made, and the very last message on screen/serial console is
"Continuing...." The computer proceeds to boot, though nothing is
shown on the console. So I don''t get to access the xen host over
serial console.
Relevant settings:
grub.conf:
serial --unit=0 --speed=115200
terminal --timeout=5 serial console
title Xen 2.0.7 / Linux Kernel 2.6.11.12-xen0
root (hd0,0)
kernel /xen.gz dom0_mem=262144 com1=115200,8n1
module /vmlinuz-2.6.11.12-xen0 ro root=/dev/VolGroup01/LogVolRoot
nousb console=xencons0 console=tty0
module /initrd-2.6.11.12-xen0.img
Dell SC1425 "Console Redirection After Boot..." -- enabled/disabled
doesn''t matter
8250 Serial Driver compiled in.
When adding console=ttyS0, the message indicating press CTRL-a three
times appears and boot stops there. Pressing CTRl-a 3x does nothing.
If it helps, this message appears during the kernel boot:
WARNING: failed to register Xen virtual console driver as
''ttyS0''
Any advice?
Thanks!
gino ledesma
_______________________________________________
Xen-users mailing list
Xen-users@lists.xensource.com
http://lists.xensource.com/xen-users
Gino LV. Ledesma wrote:> Has anyone encountered a situation where the boot output stops after > switchroot is made? What happens in my instal is that xen''s serial > console output stops at the moment the WARNING message about tls is > made, and the very last message on screen/serial console is > "Continuing...." The computer proceeds to boot, though nothing is > shown on the console. So I don''t get to access the xen host over > serial console.> module /vmlinuz-2.6.11.12-xen0 ro root=/dev/VolGroup01/LogVolRoot > nousb console=xencons0 console=tty0This might have something to do with it. It''s not "xencons0", XenoLinux sees it as ttyS0. Also, if you want the output of init to go to ttyS0 (so your initscripts'' startup messages show up there), specify it second, not first.> 8250 Serial Driver compiled in.The Xen hyperkernel has to take possession of the serial port, so building in the 8250/16550 serial driver will break things. You shouldn''t enable it.> When adding console=ttyS0, the message indicating press CTRL-a three > times appears and boot stops there. Pressing CTRl-a 3x does nothing.Yeah, not surprising. I''m rather surprised it doesn''t blow up all the time, actually, and worse than that.> If it helps, this message appears during the kernel boot: > > WARNING: failed to register Xen virtual console driver as ''ttyS0''Yep. Not surprising at all. -- Derrik Pates demon@devrandom.net _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
Thanks a lot, Derrik I left xencons0 after scouring the net for sample config files. Also, I tried setting console=tty0,ttyS0 once before and that didn''t work either. Anyhow, I rebuilt the kernel without the 8250 serial driver, corrected the grub config (put console=tty0 then console=ttyS0) and rebooted. Everything''s working fine now. Many thanks once again! gino ledesma On 8/16/05, Derrik Pates <demon@devrandom.net> wrote:> Gino LV. Ledesma wrote: > > Has anyone encountered a situation where the boot output stops after > > switchroot is made? What happens in my instal is that xen''s serial > > console output stops at the moment the WARNING message about tls is > > made, and the very last message on screen/serial console is > > "Continuing...." The computer proceeds to boot, though nothing is > > shown on the console. So I don''t get to access the xen host over > > serial console. > > > module /vmlinuz-2.6.11.12-xen0 ro root=/dev/VolGroup01/LogVolRoot > > nousb console=xencons0 console=tty0 > > This might have something to do with it. It''s not "xencons0", XenoLinux > sees it as ttyS0. Also, if you want the output of init to go to ttyS0 > (so your initscripts'' startup messages show up there), specify it > second, not first. > > > 8250 Serial Driver compiled in. > > The Xen hyperkernel has to take possession of the serial port, so > building in the 8250/16550 serial driver will break things. You > shouldn''t enable it. > > > When adding console=ttyS0, the message indicating press CTRL-a three > > times appears and boot stops there. Pressing CTRl-a 3x does nothing. > > Yeah, not surprising. I''m rather surprised it doesn''t blow up all the > time, actually, and worse than that. > > > If it helps, this message appears during the kernel boot: > > > > WARNING: failed to register Xen virtual console driver as ''ttyS0'' > > Yep. Not surprising at all. > > -- > Derrik Pates > demon@devrandom.net >_______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
On Tue, 16 Aug 2005, Derrik Pates wrote:> Gino LV. Ledesma wrote: > > Has anyone encountered a situation where the boot output stops after > > switchroot is made? What happens in my instal is that xen''s serial > > console output stops at the moment the WARNING message about tls is > > made, and the very last message on screen/serial console is > > "Continuing...." The computer proceeds to boot, though nothing is > > shown on the console. So I don''t get to access the xen host over > > serial console. > > > module /vmlinuz-2.6.11.12-xen0 ro root=/dev/VolGroup01/LogVolRoot > > nousb console=xencons0 console=tty0 > > This might have something to do with it. It''s not "xencons0", XenoLinux > sees it as ttyS0. Also, if you want the output of init to go to ttyS0 > (so your initscripts'' startup messages show up there), specify it > second, not first. > > > 8250 Serial Driver compiled in. > > The Xen hyperkernel has to take possession of the serial port, so > building in the 8250/16550 serial driver will break things. You > shouldn''t enable it.Actually, The situation seems pretty simple. It just isn''t documented, so it took me a while to figure it out. If you compile in the "real linux" serial drivers and/or console, then you break sharing the linux console with xen. This is because (as Gino just pointed out) that xen needs to take the serial port, and thus needs to "emulate" it for the linux console driver. If you have a scenario where you really do want to talk to a serial port from linux, then you need the serial driver in the kernel, and you need to either give up having a serial port for xen, or a serial port for linux. Actually, there is a bit of a work around. For initial setup purposes, you can have two grub configurations. One which gives the serial port to xen, and the other which gives the port to the linux kernel. That way you make sure you have xen up and happy, and then switch to using the config that lets you see your dom0 linux boot. Hope that helps someone. For me, with our remote servers, I _had_ to figure it out. -Tom _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users