setting up sendmail and pop3 on redhat 7.2

I just spent the last 4 days (and some of those nights) trying to get my redhat 7.2 new install configured to handle virtual email domains.
I found a complete lack of available references on the web, went out and purchased oreilly's sendmail and dns/bind books, tried redhat forums, etc. I have finally managed to get everything working to my satisfaction. I thought I would put up this quick log of what I did in the hopes that it helps someone else out!!

Goal: I wanted to support multiple virtual email domains on one redhat 7.2 server using sendmail. I wanted the ability to have the same usernames in any/all of those domains. I needed to have those email domains accessible to pop-3 clients.

Initial problems: the standard virtual domain configuration has the caveat that usernames from different virtual domains can not be the same. Example: you can not have [email protected] and [email protected] or pop-3 clients seem to receive the emails for all user1 accounts.

1) I set up the virtual domains using linuxconf...this was the easy part. Next I set up all the virtual domain user accounts.

2) Apparently I missed installing the imap package during my redhat install. I had done the custom install, gone through the individual packs, but either it wasn't there or I skipped over it. So I downloaded the imap pack from redhat using:
#> wget ftp://ftp.redhat.com/pub/redhat/linux/7.2/en/os/i386/RedHat/RPMS/imap-2000c-15.i386.rpm

Next I installed the package using:
#> rpm –ivh imap-2000c-15.i386.rpm

Next I edited both the ipop3 and imap service files located in /etc/xinetd.d/ folder and changed the line
disable = yes
to
disable = no

3) Now I needed to have the ability to bind specific IP's to each virtual domain and add the vpop3d server to handle my virtual domains.

I changed the ipop3 service file to bind the standard pop-3 server to my main email domain only. This was done by adding the line
bind = 10.10.254.10
to the service pop3 section. Of course, you would specify your own servers main ip.

Next for each virtual domain I needed, I appended the following section to the end of the ipop3 file.

service pop3
{
disable = no
flags = REUSE NAMEINARGS
socket_type = stream
wait = no
user = root
bind = 10.10.254.11
server = /usr/lib/linuxconf/lib/vpop3d
server_args = /usr/sbin/ipop3d
log_on_success += USERID HOST
log_on_failure += USERID HOST
}

Each section binds the vpop3d server to the virual domains ip.

I restarted the xinetd service using
#> /sbin/service xinetd restart

4) All pop-3 clients now were able to specify a distinct IP/domain-name for their email server. Their login takes the form of
[email protected] the vpop3d server uses the domainname portion to verify which virtual domain to access. [email protected] is distinct from [email protected] etc.

So this, in a nutshell is what I did. Perhaps there are easier or more efficient methods to acheiving this result, if so, please let me know.

Tazman