On 2005-11-06, at 1933, Sam wrote:


Now that my server is up and running,
two last questions:

1- I know that a bad address causes the email to bounce, but what is a
"doublebounce" exactly?

let's say a message arrives, addressed to a userid on your system which doesn't exist. that message will bounce, because the recipient mailbox doesn't exist.

now let's say that message was spam, and the Return-Path header in the message contained a forged address, and when qmail tries to deliver the bounce message, it is unable to do so. this is a doublebounce.

an interesting case is if the doublebounce message cannot be delivered, because your /var/qmail/control/doublebounceto or /var/ qmail/control/doublebouncehost files are wrong (or they don't exist, and your postmaster alias isn't working.) this is known as a "triplebounce". qmail handles triplebounces by dropping the message from the queue entirely.

the man page for qmail-send explains the doublebounceto and doublebouncehost control files. if "man qmail-send" doesn't work on your system, add the line "MANPATH /var/qmail/man" to your /etc/ man.config file so that the "man" command will know to look there to find man pages.

2- Every hour I get a message:
   from:   Cron Daemon
      To:   root
Subject: Cron <[EMAIL PROTECTED]> /home/vpopmail/bin/clearopensmtp 2>$1 > /dev/null

   Body:             /bin/sh: $1: ambiguous redirect

  How can I fix this error in redirect?

change the "2>$1" to "2>&1", as it should be.

you will see the construct "2>&1" in a lot of shell scripts- it means that whatever command is running with that modifier, the "standard error" channel (i.e. 2) is added in with the "standard out" channel (i.e. 1). in scripts run from cron, this prevents you from receiving an extra email with the error output.

"man sh" will explain this in more detail.

--------------------------------------------------
| John M. Simpson - KG4ZOW - Programmer At Large |
| http://www.jms1.net/           <[EMAIL PROTECTED]> |
--------------------------------------------------
| Mac OS X proves that it's easier to make UNIX  |
| pretty than it is to make Windows secure.      |
--------------------------------------------------


Attachment: PGP.sig
Description: This is a digitally signed message part

Reply via email to