[CentOS] several servers

[Christopher Chan]

roberto.barrientos at umag.cl wrote:
> hi, i have @server1.domain.com, #server2.domain.com, @server3.domain.com
> and @server4.domain.com and i distrib the e-mail users in that four
> servers for equal. 2 servers have:
> dovecot+sendmail+mailscanner+spamassassin+clamav+ssl/tls+squirrelmail and
> other two have:
> dovecot+postfix+amavisd+spamassassin+clamav+squirrelmail+ssl/tls, all this
> machine over https and firewall with drop rule for defect. ok, there more,
> i have one machine to receive e-mails and other machine to send e-mails.
> this is que question: i want have only one machine with https and
> squirrelmail (i have the machine) than the users can view the e-mails only
> with transparent one domain, per example, @domain.com.
> i do the method to send and receive e-mails by separate machine through
> the squirrelmail config but i don't know how i can do the transparent
> @domain.com ???
> what is the name of this method or what is the idea than i can permit to
> resolve this problem...
> thank for all..ROberto.-
> 
> 

You have two different systems which may or may not have the same 
delivery mechanism. It would be painful to try to get your current setup 
to work as you will need to add code to resolve the mailboxes and that 
usually should mean a central database of some sort containing the 
user's mailbox path data or server. Likewise,the incoming delivery 
system should also use the central database to determine path to mailbox 
or server for delivery.

If you take the server route, then the system needs to know which server 
to talk to and I guess you need the code somewhere in squirrelmail and 
appropriate routing in the incoming mail server.

If you take the path route, then you need to cross mount each other's 
mail store which could be a bad idea as one server going down could take 
out the entire cluster due to NFS not responding on the ones that are 
still up but you just need code in the mailbox creation phase as dovecot 
supports looking up mailbox path data in a sql/ldap database and so do 
many LDA available.

The best thing would be to build a new system using GFS + whatever to 
create a centralized mailstore so that you do not have to worry about 
adding code to resolve the user's server nor have to risk NFS taking out 
the entire cluster.