Method to mirror a single partition across the net

[kurt seel]

 Tell me if this helps :
http://bsdtips.utcorp.net/mediawiki/index.php/Mirroring_over_network
 If anything is wrong or unclear let me know.

Steve Kargl wrote:
> I was directed on freebsd-questions to ask my question on
> freebsd-fs, but freebsd-geom is perhaps a mosre appropriate
> list.
>
> I've read the Handbook's chapter on GEOM, gmirror(1), geom(8), ggated(8),
> and ggatec(8), and I've search the web for a solution to the following
> issue.
>
> I would like to mirror a single partition on system A to a partition on
> system B.  It would appear a combination of gmirror and ggated would work,
> but I haven't found any example on setting up two systems.
>
> To be specific, /etc/fstab on the 2 systems is 
>
> # Device                Mountpoint      FStype  Options         Dump    Pass#
> /dev/ad4s1b             none            swap    sw              0       0
> /dev/ad4s1a             /               ufs     rw              1       1
> /dev/ad4s1e             /data           ufs     rw              2       2
> /dev/ad4s1d             /usr            ufs     rw              2       2
>
> I want to mirror 192.168.0.20:/dev/ad4s1e to 192.168.0.21:/dev/ad4s1e
>
> Does the following method work?
>
> On 192.168.0.21:
>
>   # umount /dev/ad4s1e
>   # echo "192.168.0.21/24 RW /dev/ad4s1e" > /etc/gg.exports
>   # ggated
>
> On 192.168.0.20:
>
>   # ggatec create -o rw 192.168.0.21 /dev/ad4s1e
>   # gmirror label  data /dev/ad4s1e
>   # gmirror insert data /dev/ggate0
>
> and /etc/fstab becomes
>
> # Device                Mountpoint      FStype  Options         Dump    Pass#
> /dev/ad4s1b             none            swap    sw              0       0
> /dev/ad4s1a             /               ufs     rw   
>            1       1
> /dev/ad4s1d             /usr            ufs     rw              2       2
> /dev/mirror/data        /data           ufs     rw              2       2
>
> This also leads to the question that if one is (or both systems are)
> rebooted, does the mirror automagically come back on boot? 
>
>