From FRESH Ports and their website:
ISPman is an ISP management software written in perl, using an LDAP
backend to manage virtual hosts for an ISP. It can be used to manage,
DNS, virtual hosts for apache config, postfix configuration, cyrus
mail boxes, proftpd etc.
ISPMan was written as a management tool for the network at 4unet where
between 30 to 50 domains are hosted and the number is crazily growing.
Managing these domains and their users was a little time consuming,
and needed an Administrator who knows linux and these daemons
fluently. Now the help-desk can easily manage the domains and users.
LDAP data can be easily replicated site wide, and mail box server can
be scaled from 1 to n as required. An LDAP entry called maildrop
tells the SMTP server (postfix) where to deliver the mail. The SMTP
servers can be loadbalanced with one of many load balancing
techniques. The program is written with scalability and High
availability in mind.
This may not be the right software for you if you want to run a small
ISP on a single box or if you want to use this software as an LDAP
editor or a DNS management software by itself.
ISPMan is written mostly in Perl and is based on four major components. All these components are based on open standards and are easily customizable.
The LDAP directory can be replicated to multiple machines to balance the load.
The interface can run on http or https and is only available after successful authentification as an ISPMan admin. Access control to this interface can also be limited to designated IP addresses either via Apache access control functions or via ISPMan ACL.
Example : create directory for new domains, create mailbox for users, etc. These agents are a very important part of the system and are should be run continuously.
The agents are run via a fault taulerant services manager called « daemontools » that makes sure that the agents recovers immediately in case of any failure.