Re: slapd-meta as a proxy for a monolithic namespace

[Pierangelo Masarati <masarati@aero.polimi.it>]

On 04/24/2013 07:45 AM, Hummel, Wolfgang wrote:
> Hello OpenLDAP community,
>
> we are currently planning for a largescale directory with
> > 1 Bio. entries in a single namespace.
>
> The idea is to divide the DB in 10 equal sized DBs and let
> them access by slapd-meta proxies.
>
> Example:
> dn: ou=rsp1,c=de,o=mno
> entries with uid=79101234567890, 79101234567891 etc.
> 791 is always fix
>
> In our scenario each server would have 100 Mio. entries
> using the last digit of uid as a naturally even balanced distribution mechanism.
>
> Here are the questions:
>
> - is slapd-meta a feasible approach for this scenario ?
> - how could the slapd.conf for the proxy look like ?
>
> Here is a (non working) example with 2 backend servers.
> What is wrong about it ?
> ...
> moduleload      back_meta
> moduleload      back_ldap
> ...
> #######################################################################
> # Meta database
> #######################################################################
> database meta
> suffix " ou=rsp1,c=de,o=mno"
> dncache-ttl forever
> lastmod off
> rootdn "cn=admin,ou=rsp1,c=de,o=mno"
> rootpw secret
> network-timeout 1
> uri    "ldap://10.11.12.170/ ou=rsp1,c=de,o=mno"
> rewriteEngine on
> #rewriteContext searchFilterAttrDN
> rewriteContext searchFilter
> rewriteRule '^uid=[0-9]{11}1,.*' 'ldap://10.11.12.170/%0' ':@'
> uri    "ldap://10.11.12.180/ ou=rsp1,c=de,o=mno"
> rewriteEngine on
> #rewriteContext searchFilterAttrDN
> rewriteContext searchFilter
> rewriteRule '^uid=[0-9]{11}2,.*' 'ldap://10.11.12.180/%0' ':@'

This syntax is not valid.  Assuming the uid is in the DN of your 
entries, an option is to use something like (oversimplified)

database meta
suffix " ou=rsp1,c=de,o=mno"

uri "ldap://10.11.12.170/ou=rsp1,c=de,o=mno";
subtree-include dn.regex="^uid=[0-9]+0,ou=rsp1,c=de,o=mno$"

uri "ldap://10.11.12.180/ou=rsp1,c=de,o=mno";
subtree-include dn.regex="^uid=[0-9]+1,ou=rsp1,c=de,o=mno$"

uri "ldap://10.11.12.190/ou=rsp1,c=de,o=mno";
subtree-include dn.regex="^uid=[0-9]+2,ou=rsp1,c=de,o=mno$"

and so on.

p.

--
Pierangelo Masarati
Associate Professor
Dipartimento di Scienze e Tecnologie Aerospaziali
Politecnico di Milano