Re: chaining replication to setup a delta backup scheme

[Quanah Gibson-Mount <quanah@stanford.edu>]

--On Tuesday, November 11, 2003 5:55 PM -0500 james liang 
<blueyonder@excite.com> wrote:

> Hi,
>
> Is it possible to have openldap replicate in the following manner?
> diagram 1:
> A -> B -> C
>
> The reason for this configuration is that I am thinking about building a
> system with a hot standby and an online delta backup by leveraging
> openldap's replication capability.
>
> The way this works is this.
> A will constantly replicate to B.  If A goes down B will take it's place.
>
> B will have replication turn on but slurpd TURN OFF.  This way, the
> replication log will grow throughout the day.
>
> At mid night, a cron job will copy the replication log from B to C and
> name it with today's date.  In addition, the cron job will also apply the
> replication log from N days ago to the slapd running on C.  In other
> words, the slapd on C is N days behind and there are N number of
> replication log file.  Each replication log file contains the change
> delta of one day.
>
> In the above system:
> A - primary
> B - standby
> C - N day delta backup

Why not just export the master's database once a day, if all you care about 
are the last day's changes? and have B&C be replica's of A?

--Quanah

--
Quanah Gibson-Mount
Principal Software Developer
ITSS/TSS/Computing Systems
ITSS/TSS/Infrastructure Operations
Stanford University
GnuPG Public Key: http://www.stanford.edu/~quanah/pgp.html