Posted by Tim Roberts on 12/16/05 10:05

gordonb.04ddv@burditt.org (Gordon Burditt) wrote:
>
>>I have a very big problem.
>>I must send a single mail to multiple receivers. The number of
>>receivers are very big: approximately 6000 users, but this number
>>increase each year.
>>I find a lot of suggestion: insert all e-mail address (or part of them)
>>in the field BCC.
>
>SMTP is supposed to support a minimum of 50 addresses for a given
>message. It is not guaranteed to go higher than that.

Where did you read that? Wherever it was, I wouldn't trust anything else
that it says. RFC2821 clearly says:

The second step in the procedure is the RCPT command.
RCPT TO:<forward-path> [ SP <rcpt-parameters> ] <CRLF>
...
This step of the procedure can be repeated any number of times.

>Some UNIX servers may not honor a command-line length longer
>than 10K or 20K, which will be violated with 6000 users.

This has absolutely nothing to do with command lines.

>Note that your host may not be the only one enforcing limits. If,
>for example, you send to 1,000 addressees, your host might accept
>that, but if there's 60 in that batch going to sol.com, sol.com's
>server might refuse it for too many addressees.

If they do so, they are violating RFC2821.
--
- Tim Roberts, timr@probo.com
Providenza & Boekelheide, Inc.

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