Magical HDD Space Doubling! <wonky bsdlabel?>

Kevin D. Kinsey, DaleCo, S.P. kdk at daleco.biz
Mon Oct 4 09:53:11 PDT 2004


The other day I decided to dispose of a drive's worth of WinNT data
in order to make more FreeBSD machines in the world (cheer!)

In the past I've often used sysinstall for this purpose, so I decided
to try the other method suggested by the handbook.  I think I got
a little funky with bsdlabel, though.  Check this out:

    % dmesg | grep ad
    GEOM: create disk ad0 dp=0xc5f54660
    ad0: 38166MB <ST340014A> [77545/16/63] at ata0-master UDMA100
    GEOM: create disk ad1 dp=0xc5f54360
    ad1: 190782MB <WDC WD2000JB-00GVA0> [387621/16/63] at ata0-slave UDMA100
    GEOM: create disk ad3 dp=0xc6020960
    ad3: 38166MB <ST340015A> [77545/16/63] at ata1-slave UDMA33
    Mounting root from ufs:/dev/ad0s1a

Note that both ad1 and ad3 report 38166 MB disks.

Now, the only thing I intended to be different on the
new disk (ad3) was that it be "dangerously dedicated"
and have its own /tmp partition (ad1 has tmp on /).

However:

% df -h
Filesystem    Size   Used  Avail Capacity  Mounted on
/dev/ad0s1a    989M   151M   759M    17%    /
devfs               1.0K   1.0K     0B   100%    /dev
/dev/ad0s1e    34G    20G    11G    66%    /usr
/dev/ad0s1d   989M   275M   635M    30%    /var
/dev/ad1s1d   180G    60G   106G    36%    /backup
/dev/ad3a       36G   614M    33G     2%    /mnt
/dev/ad3b      496M    29M   427M     6%    /mnt2
/dev/ad3d      989M   273M   637M    30%    /mnt3
/dev/ad3e      34G    20G    11G    66%    /mnt4

So, ad3 is ~72GB?? ... I'd gladly take the extra space,
but it can't really be there, can it?

Here's the bsdlabel output, and a uname.  Can
anyone tell me what I did wrong (other than the obvious,
being "proceeding to use bsdlabel without a thorough handle
on what I was doing ... :-o )

% sudo bsdlabel ad0s1
# /dev/ad0s1:
8 partitions:
#        size   offset    fstype   [fsize bsize bps/cpg]
  a:  2097152        0    4.2BSD     2048 16384 28552
  b:  1048576  2097152      swap                   
  c: 78156162        0    unused        0     0         # "raw" part, 
don't edit
  d:  2097152  3145728    4.2BSD     2048 16384 28552
  e: 72913282  5242880    4.2BSD     2048 16384 28552

% sudo bsdlabel ad3
# /dev/ad3:
8 partitions:
#        size   offset    fstype   [fsize bsize bps/cpg]
  a:  2097152        0    4.2BSD     2048 16384 28552
  b:  1048576  2097152      swap                   
  c: 78165360        0    unused        0     0         # "raw" part, 
don't edit
  d:  2097152  3145728    4.2BSD     2048 16384 28552
  e: 72913282  5242880    4.2BSD     2048 16384 28552

The only difference in the labels is ad3c, which I increased
manually (trial & error) because bsdlabel kept complaining
"partition c doesn't cover entire unit" until I got up to
78165360 ...

%uname -aFreeBSD archangel.daleco.biz 5.2.1-RELEASE-p3
FreeBSD 5.2.1-RELEASE-p3 #2: Fri Apr 23 16:39:28 CDT 2004    
root at archangel.daleco.biz:/usr/obj/usr/src/sys/GENERIC  i386

[Gee, I thought I'd built world since then...]

Kevin Kinsey
DaleCo, S.P.


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