# Unable to find device node for /dev/xxx in /dev!



## swoop (Jan 11, 2011)

Hi all

I'm  trying to install FreeBSD v8.1 to be my file server and more but when setting slide and label I get the message 
	
	



```
Unable to find device node for /dev/adxxx in /dev!
```

I've several treads like
http://forums.freebsd.org/showthread.php?t=20609
http://forums.freebsd.org/showthread.php?t=5288

but I still haven't found out how to deal with it. I Have tried every possible way I could find to delete, overwrite, wipe my old partition but nothing helps.

Any hints? Thanks a lot for your time.

PS, have to trouble to understand why FreeBSD sets my disk to AD0 when BIOS sees my disk as IDE Channel 2 Master. Normally I would set my boot disk as IDE 0 (Channel 0, Master) but then FreeBSD sets the disk as AD4. Have I missed something here?


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## swoop (Jan 11, 2011)

I just tried to use the Ubuntu drive tool as mentioned in this tread:
http://forums.freebsd.org/showthread.php?t=18400

but same thing happens after created 1 slice and the partitions.

Sorry to the moderators that I by mistake created 2 posts.


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## wblock@ (Jan 11, 2011)

Was Windows 7 or some other GPT partitioning scheme on that drive before?

Boot with the 8.2 livefs CD, use
`# gpart list`

to see the devices, then use

`# sysctl kern.geom.debugflags=16`
`# gpart destroy -F ad0`

(Substitute ad2 or ad4 or whatever showed in the list above for "ad0".)

dd'ing zeros to the first 35 blocks and last 35 blocks on the drive should also work, but it's a pain to figure out the last sectors:
`# sysctl kern.geom.debugflags=16`
`# file -s /dev/ad0`

```
/dev/ada0: x86 boot sector; partition 1: ID=0xa5, active, starthead 1, startsector 63, 1465149105 sectors, code offset 0x31
```

1465149105 - 36 is 1465149069 (subtracted 36 to allow for off-by-one).

Erase the first 35 blocks:
`# dd if=/dev/zero of=/dev/ad0 bs=512 count=35`
Erase the last 35 blocks:
`# dd if=/dev/zero of=/dev/ad0 bs=512 seek=1465149069`

Untested.  file(1) may not produce useful output from a livefs CD if the magic(5) file is not present.


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## jb_fvwm2 (Jan 11, 2011)

I encountered that error.  Search the forum for
geom_mbr, geom_label, and geom_bsd (.ko). In case that
...
^^ that answer occurs here weekly it seems. Sometimes it is the fix) 
...
does not fix it (in other words, fixes available if
the drive is the only one on any IDE channel besides the
cd-rom drive...), maybe you can remove the drive and
install from another machine, replace the drive and 
edit its fstab (can be done, not easy enough to explain.)
OTOH maybe you can solve it without this post.


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## swoop (Jan 12, 2011)

Thanks so much both of you. Now I'm finally got started with the installation


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## wblock@ (Jan 12, 2011)

Good, but could you identify what solved your problem?


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## FestusHagen (Apr 19, 2011)

wblock said:
			
		

> Boot with the 8.2 livefs CD, use
> `# gpart list`
> 
> to see the devices, then use
> ...



I know this thread is a bit old, I just wanted to say "Thanks" ...

This resolved my 8.2-R installation woes over a 7.1-R installation ... It listed /dev/ad0((s1),a,b,d,e) as expected as well as what sysinstall listed however commit would fail with the "Unable to find ..." error, it all looked right, didn't work.

After the above steps the installation went flawless!

So again, Thanks all!

-Enjoy
fh  : )_~


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