gmirror and partitioning

[Gayn Winters]

> From: Nagy László Zsolt [mailto:nagylzs at freemail.hu] 
> Sent: Tuesday, May 16, 2006 8:27 AM
> To: gayn.winters at bristolsystems.com; freebsd-questions at freebsd.org
> Subject: Re: gmirror and partitioning
> 
> 
> 
> > Laszlo,
> >
> > You're making gmirror way too difficult.  In short, install 
> FreeBSD with
> > however many partitions you want, then install gmirror and replicate
> > your disk to the second disk.
> >
> > The standard howto documents are:
> >
> > http://dannyman.toldme.com/2005/01/24/freebsd-howto-gmirror-system/
> >
> > http://www.onlamp.com/pub/a/bsd/2005/11/10/FreeBSD_Basics.html
> >
> > http://people.freebsd.org/~rse/mirror/
> >
> > I've used Danny's and Ralf's (the first and third).  
> Danny's is simpler,
> > but Ralf's has the advantage that it can be done remotely.  Danny's
> > website now recommends Dru's (the second).  You may want to try that
> > first.
> >
> > Let us know how it goes,
> >   
> I tried the second link, as you suggested. It does not work for me. I 
> have to identical disks on /dev/ad10 and /dev/ad8. I have installed 
> FreeBSD on /dev/ad10 and I initialized gmirror on that disk. Here is 
> what df says:
> 
> backupserver# df -h
> Filesystem Size Used Avail Capacity Mounted on
> /dev/mirror/gm0s1a 4.8G 34M 4.4G 1% /
> devfs 1.0K 1.0K 0B 100% /dev
> /dev/mirror/gm0s1e 9.7G 12K 8.9G 0% /tmp
> /dev/mirror/gm0s1f 115G 261M 106G 0% /usr
> /dev/mirror/gm0s1d 9.7G 232K 8.9G 0% /var
> backupserver# swapinfo
> Device 1K-blocks Used Avail Capacity
> /dev/mirror/gm0s1b 5242880 0 5242880 0%Bristol Systems Inc.
714/532-6776
www.bristolsystems.com 
> backupserver#
> 
> 
> Then I try to add the ad8 device:
> 
> backupserver# gmirror insert gm0 /dev/ad8
> Provider ad8 too small.
> backupserver#
> 
> But of course this is not true. ad8 and ad10 are identical 
> 160GB SATA disks.
> What am I doing wrong? Please help.
> 
> Laszlo

Hi Laszlo,

Well it looks like you've got gm0 up and running.  I assume you've
edited /etc/fstab so that it boots cleanly.  My first thought is that
you need to zero ad8 to make sure gmirror isn't confused.  Try that (dd
if=/dev/zero of=/dev/ad8) at least for several blocks.  Then reboot and
post dmesg.

-gayn