Use mdb over hdb

[mikefaille]

«The mdb backend to slapd(8) is the recommended primary backend for a
normal slapd database. It uses OpenLDAP's own Lightning Memory-Mapped
Database (LMDB) library to store data and is intended to replace the
Berkeley DB backends.

It supports indexing like the BDB backends, but it uses no caching and
requires no tuning to deliver maximum search performance. Like hdb, it
is also fully hierarchical and supports subtree renames in constant
time.»
http://www.openldap.org/doc/admin24/backends.html

[mikefaille]

Note: The hdb backend has superseded the bdb backend, and both will soon be deprecated in favor of the new mdb backend. See below.
http://www.openldap.org/doc/admin24/backends.html

[osixia]

Hi,
thanks for the pull request. It's a great idea.

I saw that the replication ldif files are impacted,
I guess this will break the configuration if the image is used with an existing HDB backend ?

So i'm considering adding an LDAP_BACKEND environment variable to let people choose between hdb and mdb (the default) to bootstrap a new database but this variable could also be used in the replication files to keep it working with existings HDB databases.

is this would be ok for you ?

[mikefaille]

@osixia It sounds correct to me ! (sorry for my latency)
I suggest give major version for this mdb on master branch. And having old version branch using hdb.

Maybe, you can use version 1.2.x for mdb. And keeping version 1.1.x for hdb.

[osixia]

merged in 1.1.3