Failover LDAP Mode with Dovecot

PROBLEM
My LDAP uses multiple hosts and I want to add them to my Atmail configuration.

ENVIRONMENT

• On-Premise Server + WebMail Installations: Version 6.0 > Current Version

CAUSE
Some LDAP implementations use multiple hosts. Because of this, you may need to define fallback hosts for when your main authentication point fails. Follow the following steps:

RESOLUTION

1. If LDAP is not yet configured, set it in WebAdmin > Settings > Global Settings

2. Duplicate the LDAP authentication file:

   cp /usr/local/atmail/mailserver/etc/dovecot-ldap.conf /usr/local/atmail/mailserver/etc/dovecot-ldap-fallback.conf

3. Open the main dovecot.conf file (/usr/local/atmail/mailserver/etc/dovecot.conf) and find this block:

   passdb ldap {
   args = /usr/local/atmail/mailserver/etc/dovecot-ldap.conf
   }

4. Open the secondary ldap auth file ( /usr/local/atmail/mailserver/etc/dovecot-ldap-fallback.conf ), and modify this line to your secondary host:

   hosts = 192.168.0.2

5. Duplicate the block with the second filename:

   passdb ldap {
   args = /usr/local/atmail/mailserver/etc/dovecot-ldap.conf
   }
    
   passdb ldap {
   args = /usr/local/atmail/mailserver/etc/dovecot-ldap-fallback.conf
   }

6. Restart Atmail:

   % /etc/init.d/atmailserver restart