RE: Need new replica configuration without shutting down slapd

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

> -----Original Message-----
> From: owner-openldap-devel@OpenLDAP.org
> [mailto:owner-openldap-devel@OpenLDAP.org]On Behalf Of Ganesan R

> Btw, your slapd.conf backend sounds quite interesting. Do you have a draft
> design and/or code that I can look at?

Nothing substantial yet. I have code to read the slapd.conf and write to it
while attempting to preserve location of comments and such. There is a lot
in slapd that needs to be modified to make it safe. (e.g., mutex locks for
the schema structures, that sort of thing.) This is something that was
scribbled more than "designed." I'll post more on it as it matures.

> > However, depending on
> > what DBM library you use, it may not be possible to access the database
> > while slapd is running. For example, if back-ldbm is using gdbm, the
> > database will be opened with a write-lock. If you use gdbm in another
> > application, it should be unable to obtain a read-lock on the
> database. In
> > general, with back-ldbm, only the slapd process should have
> access to the
> > database.

> What alternative is there to get at all the attributes (including
> operational attributes like creationTimeStamp) of a database? I need a way
> to essentially create a replication log for the entire database. May be
> slurpd can do a "normal" ldap search on the localhost with a special
> control?

Well as you already noted, you can use ldapsearch. I forgot that back-ldbm
also has a "dbnolocking" config keyword which can be used to turn off
locking for the database. I suppose you could run with this if you needed
to, although you open the door to a host of unknown troubles using this.

back-bdb in the HEAD stream is getting closer to maturity. It supports finer
grained locking than back-ldbm, so it's feasible for other tools to operate
on the database while slapd runs. However, the code for this backend is in a
fairly continual state of flux, so I can't recommend it for anything more
than experimentation at this point. (But if you'd like to bang on it and see
where it falls apart, go ahead......)
  -- Howard