[BlueOnyx:06266] Help with webmail predicament: moving web to different server, keeping email on existing

[Jim Dory]

  I am moving our website off to a new hosting company, so 
nomealaska.org will be on a different server, different IP address. We 
are keeping our email server on the existing in-house server however, 
and unfortunately it is also named nomealaska.org.

When traveling we access our work email by logging into 
nomealaska.org/webmail. That redirects to 
https://www.nomealaska.org/webmail. Here is what the new hosting company 
suggested we do to handle keeping our ability to log into webmail:

"

Since the overall domain of nomealaska.org will
point to our web server, the address https://www.nomealaska.org/webmail
will no longer work as it does in its current form.  On your DNS server,
we'll probably have to setup something like https://mail.nomealaska.org
so that it points to the IP address of your mail server.  We can then
add a redirect for http://www.nomealaska.org/webmail so that it routes
to your server.  That will mean registering a new ssl certificate for
your mail server so that it runs on https://mail.nomealaska.org.

"

I'm not sure what all I need to do to make this change. In my 
/etc/httpd/conf.d/blueonyx.conf file I have this:
RewriteEngine On
RewriteCond %{HTTP_HOST}                ^([^:]+)
RewriteCond %{DOCUMENT_ROOT}            !-d
RewriteRule .*                          
https://%1:444/error/forbidden.html [L,R]
RewriteCond %{HTTP_HOST}                ^([^:]+)
RewriteRule ^/admin/?$                  
https://www.nomealaska.org:81/login.php [L,R]
RewriteCond %{HTTP_HOST}                ^([^:]+)
RewriteRule ^/siteadmin/?$              
https://www.nomealaska.org:81/login.php [L,R]
RewriteCond %{HTTP_HOST}                ^([^:]+)
RewriteRule ^/personal/?$               
https://www.nomealaska.org:81/login.php [L,R]


Assume I'll maybe want to make some changes there such as 
https://mail.nomealaska.org in place of existing?
Is this the easiest/best way of handling this? I have several users who 
only use webmail (squirrelmail) for accessing their accounts so they 
have email stored on the server. Hate to be much of a disruptor for them.

Advice warmly welcomed. A nice outline of steps involved?
cheers, JD

-- 
Jim Dory
Engineering
City of Nome
PO Box 281
102 Division St.
Nome, AK 99762
907.443.6604

http://www.nomealaska.org