Windows Server - Error Creating Mirror on Windows 2003 Server

Asked By Mike Schumann on 07-Oct-07 01:24 PM
I created a mirror on my new Windows 2003 Server system.  Both disks are
identical 160GByte IDE drives.

When I created a mirror, I got the following error message:

target disk.  Verify your arcpath listings in file boot.ini or through the
bootcfg.exe utility"

I'm a novice at this and am quite clueless on what to do to make sure that
if my primary disk fails, I can still boot from the mirrored drive.

Any help would be appreciated.

Mike Schumann

Pegasus \(MVP\) replied on 07-Oct-07 02:37 PM
You need to examine the hidden file c:\boot.ini.

I suggest you also have a good think about your aim in
this exercise. If you're installing a mirror because you
need to run your server with a very high availability, even
in case a disk should fail, fine (although a RAID array
would probably be far superior).

However, most problems that bring down a server are
caused by operator mistake, file corruption, an update
that's gone wrong or some software incompatibility.
Have a look at a few posts in this newsgroup, e.g. at
this one: "URGENT - Server 2003 lost almost everything".
In all of these cases a mirror will not help you at all but
a good backup process or imaging process will, e.g.
Acronis DriveImage.

Note also that your backup schemes, including mirrors,
are largely useless unless you test them immediately
after you have configured them, and then again twice
each year. There are many posts here from server
admins who are utterly baffled when one of their mirror
disks fails and they have to boot the server from the
other disk, with the boss breathing down their neck.
They have never done it before and their boss wonders
why he spent the money on a redundant system that
involves a lengthy downtime the first time there is a problem.
Mike Schumann replied on 07-Oct-07 05:50 PM
I definitely agree with you on backups, etc.  I'm only mirroring to minimize
a potential problem caused by a drive failure, and hopefully to get some
performance advantage on disk reads.

Mike Schumann
Mike Schumann replied on 07-Oct-07 06:13 PM
I solved the problem and thought that I would post the answer here for
others who run into the same situation.

From researching various on-line postings, I suspected that the problem was
either caused by the boot.ini file being read only, or the fact that the
mirror disk drive had never been set up with a boot sector (I initially
tried to mirror to this drive when it was a virgin drive).

I did two things (I'm not sure which fixed the problem):

1.  I unlinked the mirror.
2.  I executed "attrib -s -h -r \boot.ini"
3.  I created a primary partition on the drive that I wanted to use for the
4.  I deleted the primary partition
5.  I created the mirror - VOILA - NO ERROR msg
6.  I reset the default attributes on boot.ini by executing "attrib +s +h +r
\boot.ini"  (The boot.ini file had a new entry for the mirror drive).

After the mirrors sychronized, I was able to power down each drive
seperately and still boot (restoring the mirror between tests).

I hope this helps anyone else with the same issue.

Mike Schumann
Pegasus \(MVP\) replied on 07-Oct-07 06:22 PM
I doubt whether creating/deleting a partition had any effect.
On the other hand the boot.ini is not write-protected by default,
so this would be a more likely cause. If it is then Microsoft
were sloppy: The mirroring tool should take appropriate
action if it encounters a write-protected file.