Email Server Solution

Steve Buehler steve at ibapp.com
Wed Aug 3 14:52:57 UTC 2005


At 08:26 AM 8/3/2005, you wrote:

>I am by no way a sendmail expert but it sounds like Masquerading is what
>you want to do if you are using native sendmail. But I have done
>masquerading in the past and basically how it works is that anyone that
>connects to it for SMTP communications would have their domain name
>changed to whatever the masquerading option is set to in the mc or the
>cf file. If it is in the MC all you would need to do is modify the
>masquearding lines which are commented out then run an m4 against it to
>compile the MC. Do you want all outbound messages to come out as a
>single domain or do you want to have multiple out bound domains?

         It is not the issue of sending it from a different domain 
itself.  The problem would be that I want it to send out through that 
domains IP address.  Lets say I have the following setup
server1: 192.168.1.1 (this is the name of the server that hosts all 
of the domains and the IP address of the server0
domain1: 192.168.1.2 (a domain on the server with its own static IP)
domain2: 192.168.1.3 (another domain on the server with its own static IP)
         When an email gets sent out from one of those domains, it 
always goes out on server1's IP.  So if one of the domains is doing 
something that could get us blocked, it blocks all domains on that 
server.  We don't have any customers that spam....not on purpose 
anyway.  But a few might have viruses that would send out email 
through their POP account on us with viruses or just spam.  It then 
gets caught as spam by an address that it is sending to and can get 
us blocked by the RBL lists or the CBL lists.  When it happens, these 
lists don't block the domain name, they put a block on the IP of the 
server it came from.  Since all emails on the server go out from the 
servers IP instead of the domains IP, it blocks the whole server 
instead of just the offending site.  That can really tick off the 
rest of the clients on the server.
         We also have the problem of ignorant people on AOL and other 
ISP's that order through one of the stores that are on our 
server.  When they order, they are told that they will get a 
confirmation email.  But they aren't to bright or just plain hit the 
wrong button when they get the email and mark the confirmation as 
spam.  That can then get us blocked if it is done more than a few 
times, which happens with AOL customers.  The majority of whom don't 
even know where their computers on/off switch is.  When this happens, 
again, the whole server gets blocked instead of just the domain the 
email came from.
         Another issue is that we have customers that get their email 
coming in for their domain forwarded to their AOL account.  If they 
get any spam, it gets forwarded to there AOL account and then they 
mark it as spam there.  From what AOL told me, that can get our 
server blocked too because it can block all IP's that are in the 
headers of the email message.  As soon as we found this out, we will 
no longer allow our customers to forward their emails to an AOL 
account.  They can pick up their email on our server, or have it 
forwarded to another ISP, but not to AOL.

>That would determine how many sendmail servers you would need to have
>and I would assume the control panel would allow you send messages
>through a different SMTP server then the one they control.

If masquerading doesn't change the email to go out from the IP of the 
domain instead of the IP of the server itself, then it won't do us 
any good.  Will it do what we need by sending the email out from the 
domains IP instead the servers IP?

>What does your vendor support say about this question?

         They don't say.  I have posted the problem in their Forum, 
without any response.  To ask them directly would cost us for a 
support ticket.  And the boss is being cheap about it.  Except that 
it is costing more because we are buying another server to use as an 
Smart_Host email server.
         I need to get on the sendmail mailing list and figure out 
how to use the new email server as an incoming MX server for all the 
domains and then forward them on to the real server where the clients 
would pick up their email from.

Thanks
Steve




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