Hello, is possbile that rpcthosts or morercpthosts doesn't exists in this moment (or is not readable) - eg. user is editing/additing domain (using qmailadmin or vpopmail) ?
It's only idea. 2008/2/5, Joey Novak <[EMAIL PROTECTED]>: > Hey Guys, > > So, we have a toaster install. vpopmail, mysql etc... > > We have about 20,000 email accounts, and recently we have observed a very > strange issue. > > Occasionaly, when a customer sends a message from squirrelmail, the get a > 553 error. (This probably occurs from outlook as well, we just havan't > received any reports of it yet) The odd thing is, that if they continue to > try to send the message, eventually it goes through. Although we do have a > cluster of 4 mail servers. The problem is not unique to any of the servers. > A server will deny the message. But, 10 minutes later the same server will > accept the same message. We have been able to repeatedly re-produce the > problem using telnet, and the exact same SMTP conversation. > > Here is an example smtp conversation I captured yesterday using tcpdump. > > 220 mail.ispemailserver.com mail1 ESMTP > EHLO webmail.mylifeline.net > 250-mail.ispemailserver.com mail1 > 250-STARTTLS > 250-PIPELINING > 250-8BITMIME > 250-SIZE 10000000 > 250 AUTH LOGIN PLAIN CRAM-MD5 > MAIL FROM:<[EMAIL PROTECTED]> > 250 ok > RCPT TO:<[EMAIL PROTECTED]> > 553 5.7.1 sorry, that domain isn't in my list of allowed rcpthosts (chkuser) > > And here is the same conversation today, but without the 553 error: > > 220 mail.ispemailserver.com mail1 ESMTP > EHLO webmail.mylifeline.net > 250-mail.ispemailserver.com mail1 > 250-STARTTLS > 250-PIPELINING > 250-8BITMIME > 250-SIZE 10000000 > 250 AUTH LOGIN PLAIN CRAM-MD5 > MAIL FROM:<[EMAIL PROTECTED]> > 250 ok > RCPT TO:<[EMAIL PROTECTED]> > 250 ok > > There are no hints or clues in the logs that I have been able to find. > > Joey > -- > -Joey > > C) 803-409-9969 > W) 757-233-0834 -- Lampa
