Scroll to navigation

() ()
System Administration Commands etrn(8)

NAME etrn - start mail queue run

SYNOPSIS etrn [-v] server-host [client-hosts]

DESCRIPTION SMTP's ETRN command allows an SMTP client and server to interact, giving the server an opportunity to start the pro­ cessing of its queues for messages to go to a given host. This is meant to be used in start-up conditions, as well as for mail nodes that have transient connections to their ser­ vice providers.

The etrn utility initiates an SMTP session with the host server-host and sends one or more ETRN commands as follows: If no client-hosts are specified, etrn looks up every host name for which sendmail(1M) accepts email and, for each name, sends an ETRN command with that name as the argument. If any client-hosts are specified, etrn uses each of these as arguments for successive ETRN commands.

OPTIONS The following option is supported:

-v The normal mode of operation for etrn is to do all of its work silently. The -v option makes it verbose, which causes etrn to display its conversations with the remote SMTP server.

ENVIRONMENT No environment variables are used.

FILES /etc/mail/ sendmail configuration file

SEE ALSO sendmail(1M), RFC 1985.

CAVEATS Not all SMTP servers support ETRN.

CREDITS Leveraged from David Muir Sharnoff's script. Chris­ tian von Roques added support for args and fixed a couple of bugs.

AVAILABILITY The latest version of etrn is available in the contrib directory of the sendmail distribution through anonymous ftp at

AUTHOR John T. Beck <>

August 8, 2020