System Administration Commands etrn(8)
etrn - start mail queue run
etrn [-v] server-host [client-hosts]
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
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.
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.
No environment variables are used.
/etc/mail/sendmail.cf sendmail configuration file
sendmail(1M), RFC 1985.
Not all SMTP servers support ETRN.
Leveraged from David Muir Sharnoff's expn.pl script. Chris
tian von Roques added support for args and fixed a couple of
The latest version of etrn is available in the contrib
directory of the sendmail distribution through anonymous ftp
John T. Beck <email@example.com>