First post. I searched the site, FAQ and forums and couldn't find this info. I have two existing servers in-house, one for web and the other for email. Both run Debian. I'm using apache2, webmin, awstats, postfix, postgrey, squirrelmail and amavisd-new. These servers have been up for years but are up to date. Now, my question: How do I install ISPConfig and be sure that I don't mess something up in my current configuration? (I'm completely new to ISPConfig but an experienced admin other than that.) These are live servers. Will I need to back up, take them down, install ISPConfig and then rebuild all my services? Or can I install it and gradually give it control of each service in turn by activating settings? To put it another way, does installing ISPConfig mess with existing configuration files? Have looked at the perfect server docs but don't they don't apply to live servers.
You need to follow one of the Perfect Install guides to install server by ISPConfig requirements, than in last steps while installing ISPConfig software you need to choose Expert and join existing multi-server environment. Go to howtoforge.org and type the following query in searchbox: The Perfect Server There you can find installation for OS of your choice. There is even a manual that explains everything in easy way.