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.
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.