Re: /dev files, mfs, audio, startup etc.

[Thor Lancelot Simon <tls%rek.tjls.com@localhost>]

On Thu, Sep 04, 2008 at 11:44:22PM +0300, Aleksey Cheusov wrote:
> For some unknown reason /dev/audio, /dev/mixer and /dev/sound
> files are not present on my system.
> 
> dmesg:
>   auvia0 at pci0 dev 17 function 5: VIA Technologies VT8233A AC'97 Audio (rev 
> 0x40)
>   auvia0: interrupting at irq 10
>   auvia0: ac97: Avance Logic ALC200/ALC201 codec; headphone,
>             18 bit DAC, 18 bit ADC, Realtek 3D
>   auvia0: ac97: ext id 605<AC97_22,AMAP,SPDIF,VRA>
>   audio0 at auvia0: full duplex, mmap, independent
>   isa0 at pcib0
> 
> Q1) Why these device files are absent?

Because you somehow managed not to run the (cd dev; ./MAKEDEV all) step
when installing -- did you use sysinst, or install "by hand"?

If /dev/console is missing, init mounts an MFS on /dev at startup time
and creates a minimal set of devices there.  The problem is, it is then
hard to get at the real /dev underneath it in order to fix things.

You could either boot from install media, mount your normal / filesystem
on /mnt, then (cd /mnt/dev; ./MAKEDEV all) or try using nullfs to remount
/ like this:

        mkdir /mnt
        mount_null / /mnt
        cd /mnt/dev
        ./MAKEDEV all
        cd
        sync
        umount /mnt
        shutdown -r now

If your kernel doesn't have nullfs, you could try an NFS mount from
localhost.

-- 
Thor Lancelot Simon                                        
tls%rek.tjls.com@localhost
 "My guess is that the minimal training typically provided would only
 have given the party in question multiple new and elaborate ways to do
 something incomprehensibly stupid and dangerous."      -Rich Goldstone