Auteur: Stuart Lynne Date: À: exim-users Sujet: Re: [Exim] Opinions sought: Exim and MYSQL > 2. Specification of host, database, user, and password
> > The supplied code just had these hardcoded, which of course must be
> changed. As well as host, a port number should be settable.
>
> For the host, a global list of servers to try, like the newly
> implemented (but not yet released) ldap_default_servers seems like the
> right way to go.
Just a note. I was poking around in the openldap libldap implementation
last night and verified that if you define multiple A records for a server
(round-robin DNS) the library will automatically iterate across the list
looking for a successful connection. [Note it only attempts a single
connection to each host.]
So defining round-robin DNS to get at multiple servers achieves both load
balancing and redundancy.
If (the soon to be released) ldap_default_servers allows multiple
values the api also allows multiple host names to be passed to it.
This capability is different from round-robin in that the connection
attempts will always be in the same sequence instead of random order.
Also I am looking at testing the libldap capability for handling referrals.
This allows yet another level of indirection that is under control of the
directory servers themselves. It may be interesting to add
ldap_referral_allowed or similiar.
