>The space required for archivelogging during a hot backup shouldn't
>be anywhere near the size required to take a second copy of the database.
It wasn't a space issue, at least not directly. It's my understanding
that if we **did** run out of archive log space, we were SOL.
Again, I'm not an Oracle person, but I trust completely they guy here
who is.
>> How does the guarantee the disks in the mirror are up to date, i.e.
>> logically consistent from Oracle's point of view?
>
>It doesn't. The broken mirror is the equivalent of a crashed system.
OK, I get it.
>> This technique comes up once in a while for normal backups, too, and
>> it's never made any sense to me. It won't work any better than what dump
>> (or tar, in some cases) does now.
>
>Except that your mirror will be on a second set of disks and SCSI channels
>...
By "any better" I meant the data is no more consistent, not that there
weren't other issues (like performance). When it's come up in my hearing
in the past, it's usually been "look, there's this neat snapshot of the
system we can get for free" with the implication it's just as good as a
freshly fsck'd and sync'd disk, which it isn't. That's all I was trying
to say.
>Colin.
John R. Jackson, Technical Software Specialist, [EMAIL PROTECTED]
