> So: It appears that the facility is already present, at least at the
> ldap_open() level, though strictly this breaks the rules for the URL.
I know, but OpenLDAP views that as a bug that will be fixed in the
future, because it violates RFCs.
> However: there are other circumstances that cause deferment, namely
>
> 1. failure to bind to the host after setting up the connection
> 2. some kind of syntax error
> 3. timeout on the query
> 4. too many entries returned
>
> I don't think you't want to try another server for 2 and 4, so the
> question is: are 1 and 3 cases that are going to happen often enough in
> practice to make it worth putting in special code for them?
My patch has been discussed on the list for a while and the result was
that it may be wise to use a variable ldap_hosts, which holds a list of
hosts to try, and unqualified LDAP URLs. That way we do not break the
RFC and the URLs get shorter.
My mail system depends on the ability to use redundant LDAP
servers, because by now it is entirely controlled by LDAP (including
local_domains). Example: I change the schema and re-initialise a
local replica server. Copying the new data base to it takes a while.
It would not be acceptable to defer mail during that time.
Michael
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