RE: Splitting directory over backends

["Howard Chu" <hyc@symas.com>]

> -----Original Message-----
> From: owner-openldap-software@OpenLDAP.org
> [mailto:owner-openldap-software@OpenLDAP.org]On Behalf Of Rick van Rein

> People,
>
> Would it be possible to configure OpenLDAP such that it supports the
> separation of one tree over multiple backends?  For instance,
>
> 	                             dc=com => backend-dnssrv
> 	                  dc=example,dc=com => backend-ldbm
> 	         ou=Sales,dc=example,dc=com => backend-sql
> 	ou=ProductCatalog,dc=example,dc=com => backend-ldbm
> 	                    dc=other,dc=com => backend-ldbm
>
> The idea would be to make sales in progress viewable, and access an SQL
> database for it; while the static product catalog would be stored in LDBM,
> along with the rest of the domain.
>
> The fallback to the DNSSRV backend would be a similar thing; supporting it
> locally could be useful to offload the root.openldap.org service and
> provide quicker service to internal users.
>
> I know that LDAP allows all this.  But can I tweak/convince OpenLDAP about
> such general/weird schemes?  Wouldn't be the first time OpenLDAP is more
> flexible than what appears from reading the online docs.

The docs cover this situation. See 2.1.4 slapd.conf(5) and look for the
"subordinate" keyword. Your backends must be configured in ascending order:

> 	         ou=Sales,dc=example,dc=com => backend-sql     subordinate
> 	ou=ProductCatalog,dc=example,dc=com => backend-ldbm    subordinate
> 	                  dc=example,dc=com => backend-ldbm    subordinate
> 	                    dc=other,dc=com => backend-ldbm    subordinate
> 	                             dc=com => backend-dnssrv

There is a bug with one-level searches in the 2.1.4 subordinate code, it is
fixed in CVS and will be in 2.1.5.

  -- Howard Chu
  Chief Architect, Symas Corp.       Director, Highland Sun
  http://www.symas.com               http://highlandsun.com/hyc
  Symas: Premier OpenSource Development and Support