technical violation of RFC821 4.3 (and RFC2821 4.3.1) in ME

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technical violation of RFC821 4.3 (and RFC2821 4.3.1) in ME

Post by Chrissicom » Tue Dec 07, 2004 7:51 am

WARNING: One or more of your mailservers may be claiming to be a host other than what it really is (the SMTP greeting should be a 3-digit code, followed by a space or a dash, then the host name). This probably won't cause any harm, but may be a technical violation of RFC821 4.3 (and RFC2821 4.3.1). claims to be host

Does anyone know how I can fix this problem? There are about 15 domains hosted on the same IP using one Mail Enable Server. I cannot enter in the host name field of the SMTP settings since there are other mail servers like on the server. Is there something like "001 %host%" and %host% being replaced with the current mail server, which I can enter?

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Post by MrByte » Tue Dec 07, 2004 7:17 pm

This is something that can't be done currently as you can not bind an diffeent IP for each domain (and hence the host identification).
The Enterprise version does allow IP binding per domain, but I'm not sure if it also allows for changing the host identifier on SMTP connections....

I have the same issue, but have not had (yet) any issues with any provider rejecting mail because of that mismatch.


Post by Chrissicom » Wed Dec 08, 2004 9:18 am

Well, it would be easy set up at least different PTR Records if I had an IP for each domain, but I have many domains on the same IP using the same name servers, hence they all have the same PTR Record, since you can't make multiple PTRs for one IP. Thus other servers get a PTR different from the actual mail server domain in most cases, therefor I thought it would be good to have a host name setting in mail enable which sends the correct host name for each domain.

MTS (a US or Canadian Provider I think), Texas Instruments and sometimes AOL mail servers are causing problems with the current settings.

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Post by Kiliman » Wed Dec 08, 2004 8:00 pm

There's no way to do what you want. The SMTP greeting is sent by the server immediately up connection.

At this point, all it know is the IP address. There's is no way it could tell what domain the client is trying to send to.

I also have multiple domains on a single IP address. Here is what I do. I simply set the MX record for all my domains to be the same as the PTR record.

Since my SMTP greeting always responds with 220, which is the same as my MX and PTR, I've never had any problems with sending or receiving mail.


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