1.Can I just install a 2nd box with Bind and set it up as secondary and then somehow synchronize the records with the main Virtualmin server? Something like cpanel’s ‘dns cluster’.
Yes. Webmin has a feature called Cluster Slave Servers, and Virtualmin works with this feature very well. So you can easily have all domains replicated out to as many slaves as you like. I haven’t documented this as well as it needs to be documented however…I’ll be working on the docs some more after EA2 rolls out the door (SUSE is making my life difficult).
2.Can I run the email server from a different box and be able to synchronize the accounts based on the Virtualmin server?
Not yet. We are working on adding LDAP support for Postfix which will give this capability (but require user accounts in LDAP), and I expect this will be available in a month or less. Further down the road (maybe 3-6 months), all features will likely be “remoteable” in an easily configurable manner, allowing any aspect of a virtual account to be setup on a different server. No guarantees on the latter–it will depend on how much demand there is for it from customers. Right now, we’re focused on platform support. Everyone has a favorite platform, and so our customers are almost universally demanding support for different systems.
3.Can I move accounts accross to other servers to balance better the load?
Yes. You can backup and restore individual domains quite easily across similarly configured Virtualmin servers. You could even have the backup module create the backup file on the remote server to start with, so you don’t have to copy it manually.
4.Is it possible to use any MTA or Apache that I want? For example Qmail,Postfix and Apache2 ?
Yes, though there is a clear "Golden Path" that we are supporting most aggressively. That path will be the easiest to install, use, and have the most features. These applications will Just Work, immediately after installation. The application stack we have selected is:
Apache (the current version 2 from the OS vendor, so 2.0.53 for Fedora Core 4, for example)
Procmail with Maildir spools
PHP4 and PHP5
Usermin (also obvious!)
Plus a bunch of other stuff that is supported by the script installer module (about 25 different CGI and PHP scripts that can automatically be installed by users). In addition to the modules for Webmin and Usermin that provide access to PostgreSQL and MySQL and webmail, there are script installers for phpPgAdmin and phpMyAdmin and several webmail clients like HORDE and others. So, even within this stack of applications there is a lot of flexibility.
In short, we highly recommend you just let the installer take care of everything for you. But if you have a strong desire for some other MTA, if it is one of the currently Virtualmin configurable MTAs (Sendmail, QMail, Postfix), we’ll try to help. We will not be adding any other servers in the near future, however, such as djbdns or exim, for example. Our focus will be on adding new features, making the existing feature set easier to use, documenting the existing features more fully, and for the immediate future killing all bugs in sight. And platform support. We’ll be spending a lot of time on making the installer work flawlessly on the several platforms we’ve committed to supporting (Fedora, RHEL, CentOS, SuSE, Mandrake, FreeBSD, Debian, Ubuntu, and Gentoo on x86 and x86_64, plus RHEL and SUSE on PPC and PPC64).
I hope this helps with your plans.