My vinum scare

Yesterday, I updated my system from a 5.1-CURRENT build on 2004-01-29 to
recent source.  All of my filesystems, except for root and swap, are on
vinum volumes for flexibility in management.  After the 'installkernel'
step, I rebooted into single-user to make installworld and run mergemaster,
and this completed successfully.  Then, I rebooted to bring the system back
online.

That's when I discovered that vinum had totally lost all of its
configuration information, except for the name of the single drive ("wd120")
that I use.  Following the instructions at
http://www.vinumvm.org/vinum/how-to-debug.html, I got:

    # < log tr -d '\000-\011\200-\377'
    IN VINOkanga.honeypot.netwd120a>P.pMg_at_[obme>MBR</name>
        <geom id="0xc5e0da00">
          <class ref="0xc08ebf20"/>
          <name>da0</name>
          <rank>2</rank>
          <config>
          </config>
    <consumer id="0xc5d238c0">
      <geom ref="0xc5e0da00"/>
      <provider ref="0xc5e35000"/>
      <mode>r0w0e0</mode>
      <config>
      </config>
    </consumer>
    <provider id="0xc1dfa280">
      <geom ref="0xc5e0da00"/>
      <mode>r0w0e0</mode>
      <name>da0s4</name>

'vinum dumpconfig' reported nothing but the definition of the "wd120" drive:
no volumes, plexes, or subdisks.  Nothing.  At this point, I had a minor
heart attack.

Once I stepped back, I remembered that I *always* use 'printconfig' to write
a copy of my configuration to /etc/vinum.conf.  A quick 'vinum create'
command had me back up and running with no ill effects.

I have no idea what happened, but I ask that you trust me when I say that I
hadn't touched vinum at all during the system update.

Two lessons:

  1) Realizing that you have a backup of such critical data as your vinum
     configuration is one of the best feelings in the world.

  2) Realizing that in the event of failure of lesson #1, that you still
     have a full backup to tape from a few hours earlier, and that no matter
     *what* happens, you're only an hour away from having your system
     back...  It doesn't get much better than that.

-- 
Kirk Strauser

"94 outdated ports on the box,
 94 outdated ports.
 Portupgrade one, an hour 'til done,
 82 outdated ports on the box."