(To the original poster:)  Here is sort of a bad hack that once helped me when sending e-mail from a machine whose root disk (with /tmp) occasionally went into a read-only state, making use of sendmail etc. just impossible. It is simply shell-based, plus "nc":         (         echo "HELO "         sleep 1         echo "MAIL FROM: "         sleep 1         echo "RCPT TO:         sleep 1         echo "DATA"         sleep 1     echo "Subject:         sleep 1     echo ""         sleep 1     echo " "         sleep 1         echo "."         sleep 1         echo "QUIT"         sleep 1     ) |     nc   25  Everything in <...> needs to be replaced by actual values of course!  The key is the "nc" (netcat) command in UNIX (also OneFS), which opens a network connection to the given host and port (smtp = 25) and allows to send and receive any data over it. Here we "speak" the text-based SMTP mail protocol line by line. (You might also use telnet, probably with an "expect" script.)  Note there is no error handling in here, no retry after failure etc. And the mailhost is fixed -- no problem assuming you want to send e-mails only to few in-house addresses. Otherwise you would need to look up the server for each e-mail address, probably deal with relays,  and more or less you would arrive at something that acts like the Python mail module mentioned by Andrew.  (You could use that Python module of course, it is not Isilon-specific. Only obtaining the mail config is; you could feed in your mail params on your own instead.)  -- Peter
I am trying to send mail from my cluster using the command line. Using either the mail or mailx command. When I try to send mail the logs show the wrong relay and mail is deferred. I tried adding the correct relay to the line in /etc/mail/sendmail.cf starting with the DS. Then I tried to bounce sendmail using /etc/rc.d_disabled/sendmail onerestart... But I'm getting the same results.  Using the GUI under cluster management, email settings everything is correct and the call home seems to be working when I run a manual test.  What am I missing?
Sendmail from an Isilon cluster