title: Difference between backends and databases in Openldap
body: <p>I started learning Openldap 2.4, but I faced some concepts that I couldn’t understand well based on official administration guide. So I’m addressing those questions to the community in hope to find some good explanations.
  The first question is what the difference between backbends and databases in Openldap? Also in documentation I found something very confusing, for example in the backbends section, I tried to create an ldap backend with those instructions.</p>
  
  <p>database        ldap</p>
  
  <p>suffix          "dc=suretecsystems,dc=com"</p>
  
  <p>rootdn          "cn=slapd-ldap"</p>
  
  <p>uri             ldap://localhost/ ldap://remotehost ldap://remotehost2</p>
  
  <p>After altering my configuration directory, I found olcDatabase={1}ldap.ldif file created in cn=config folder, and no back-ldap module has been created.</p>
  
  <p>Another question, is about multiple databases definition in Openldap server, if I created two databases (for example an hdb and mdb database). How a query from Ldap client is handled by the server? The data are fetched from the both databases defined with an specific order, or there is a way to chooses which database we want to interact with?</p>
  
  <p>And finally, why in official administration guide we still find slapd.conf configuration style while it is deprecated? Is there any updated guide?</p>
  
  <p>Thanks!! </p>