UPS on ttyS0 in dom0

[Kanwar Ranbir Sandhu]

Hello All,

This is my first post to the fedora-xen list.  I've been on the
xen-users list for a few months now.

Up until this weekend, I was using xen on a RHEL 4 box to run 3 CentOS 4
domUs.  I'm now running xen on a FC5 dom0.  I had some problems during
the transition, one of which was really odd.  But, I got that fixed now,
so I'm happy - mostly.

My main reason for switching over to FC5 was so that I could use the
separate xen0 and xenU kernels (didn't want to compile my own).  I
needed the separate kernels in order to monitor my UPS, which is
connected to the external serial port (the serial port is disabled in
the xensource kernel RPM).  However, the damn thing still doesn't work -
I'm completely baffled.

Here's my current kernel config for dom0:

title Fedora Core (2.6.17-1.2174_FC5xen0)
        root (hd0,0)
        kernel /xen.gz-2.6.17-1.2174_FC5
        module /vmlinuz-2.6.17-1.2174_FC5xen0 ro root=/dev/vg00/root
xencons=tty
        module /initrd-2.6.17-1.2174_FC5xen0.img

That gives me this crap out:

kernel: WARNING: Failed to register Xen virtual console driver as 'tty1'

Very nice.  I thought that maybe I had to disable tty1 in /etc/inittab,
so I did, but the error remained.  Hoping for the best, I tried
accessing the UPS anyway, and I was handed more turd on a stick:

Sun Aug 20 18:59:33 EDT 2006  apcupsd FATAL ERROR in smartsetup.c at
line 61
Cannot open UPS port /dev/ttyS0: No such device or address
Sun Aug 20 18:59:33 EDT 2006  apcupsd error shutdown completed

Perfect.  So, I switch xencons=tty to xencons=off, but the result is the
same.  Using console=vga on the xen line didn't help either.

Incidentally, ttyS0 _does_ exist:

[root@xenmaster src]# ls -l /dev/ttyS0
crw------- 1 root root 4, 64 Aug 21 06:05 /dev/ttyS0

Does anyone have any ideas?

Regards,

Ranbir

-- 
Kanwar Ranbir Sandhu
Linux 2.6.17-1.2142_FC4 i686 GNU/Linux 
15:56:37 up 2 days, 9:26, 3 users, load average: 0.42, 0.52, 0.46

[Markus Armbruster]

Kanwar Ranbir Sandhu <m3freak(a)rogers.com&gt; writes:

[...]
>  Here's my current kernel config for dom0:
>
>  title Fedora Core (2.6.17-1.2174_FC5xen0)
>          root (hd0,0)
>          kernel /xen.gz-2.6.17-1.2174_FC5
>          module /vmlinuz-2.6.17-1.2174_FC5xen0 ro root=/dev/vg00/root
>  xencons=tty
>          module /initrd-2.6.17-1.2174_FC5xen0.img
>
>  That gives me this crap out:
>
>  kernel: WARNING: Failed to register Xen virtual console driver as 'tty1'
>
>  Very nice.  I thought that maybe I had to disable tty1 in /etc/inittab,
>  so I did, but the error remained.  Hoping for the best, I tried
>  accessing the UPS anyway, and I was handed more turd on a stick:
>
>  Sun Aug 20 18:59:33 EDT 2006  apcupsd FATAL ERROR in smartsetup.c at
>  line 61
>  Cannot open UPS port /dev/ttyS0: No such device or address
>  Sun Aug 20 18:59:33 EDT 2006  apcupsd error shutdown completed
>
>  Perfect.  So, I switch xencons=tty to xencons=off, but the result is the
>  same.  Using console=vga on the xen line didn't help either.
>
>  Incidentally, ttyS0 _does_ exist:
>
>  [root@xenmaster src]# ls -l /dev/ttyS0
>  crw------- 1 root root 4, 64 Aug 21 06:05 /dev/ttyS0
>
>  Does anyone have any ideas? 
This could well be related to the evil hackery the xen console uses to
steal a console device.  That hackery is being cleaned up, so with
a bit of luck your problem could go away soon.

I guess this reply isn't immediately helpful for you, but I figure
it's better than no reply...

[Kanwar Ranbir Sandhu]

On Wed, 2006-23-08 at 09:12 +0200, Markus Armbruster wrote:
>  This could well be related to the evil hackery the xen console uses
> to
>  steal a console device.  That hackery is being cleaned up, so with
>  a bit of luck your problem could go away soon. 
Sounds promising: colour me hopeful.  Will any of this make it into FC5?

>  I guess this reply isn't immediately helpful for you, but I
> figure
>  it's better than no reply... 
Yeah, better than nothing.  But, it means my Smart UPS will have to run
dumb.  That's a little sad.

Regards,

Ranbir

-- 
Kanwar Ranbir Sandhu
Linux 2.6.17-1.2142_FC4 i686 GNU/Linux 
08:07:41 up 3 days, 1:36, 3 users, load average: 0.20, 0.18, 0.12

[Markus Armbruster]

Kanwar Ranbir Sandhu <m3freak(a)rogers.com&gt; writes:

>  On Wed, 2006-23-08 at 09:12 +0200, Markus Armbruster wrote:
> > This could well be related to the evil hackery the xen console uses to
> > steal a console device.  That hackery is being cleaned up, so with
> > a bit of luck your problem could go away soon.
>
>  Sounds promising: colour me hopeful.  Will any of this make it into FC5? 
FC6 yes.  FC5 I don't know.