Re: Using back-ldap as a client-side proxy/cache

Ryan Steele wrote:
> Hey folks,
>
> In order to provide stability to my OpenLDAP clients in the event of a
network outage, I would like to implement some
> client-side caching. I've done some research, and have concluded that nscd
is evil and should be avoided at all costs,

It's not necesarily evil, it just doesn't work...

> and thus eventually settled on using back-ldap as a proxy and caching
mechanism on the clients.

And just to be clear, back-ldap is only a proxy. For caching support you must 
add the pcache overlay.

> Ideally, clients would
> query a local cache first, and if the information was not available,
back-ldap would then forward the connection on to
> my root OpenLDAP server(s).

That's exactly what back-ldap+pcache will do.

> However, I didn't see much information in the
admin guide with respect to such
> configurations other than a reference to the back-ldap man page, and given
that I've got no real experience with setting
> up back-ldap, I was wondering if somebody who did/does would have some
recommendations, advice, or knew of a good
> documentation source describing this sort of setup?

Generally there's not much to set up. back-ldap needs whatever information any 
client would need to communicate successfully with the remote LDAP server.

> The other question I have is that it seems most people use back-ldap with
> a
slapd.conf-style configuration, versus a
> cn=config type of setup. In this sort of circumstance, where one is not
configuring a full-on OpenLDAP server/replica,
> that seems like it might be a good thing in the interest of keeping the
client configurations simple. Nonetheless, I
> wanted to verify that it was the recommended way, since slapd.conf (in the
context of a fully fleshed-out OpenLDAP
> server) is deprecated.

It only seems that most are using slapd.conf because cn=config is new and most 
sites with existing slapd.conf deployments haven't migrated to cn=config yet. 
For new installs, just use cn=config.

-- 
   -- Howard Chu
   CTO, Symas Corp.           http://www.symas.com
   Director, Highland Sun     http://highlandsun.com/hyc/
   Chief Architect, OpenLDAP  http://www.openldap.org/project/