System Administration Commands etrn(1M)
NAME
etrn - start mail queue run
SYNOPSIS
etrn [-b] [-v] server-host [client-hosts]
DESCRIPTION
SMTP's ETRN command allows an SMTP client and server tointeract, 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 options are supported:-b System boot special case. Make sure localhost is
accepting SMTP connections before initiating the SMTPsession with server-host.
This option is useful because it prevents race condi-
tions between sendmail(1M) accepting connections andserver-host attempting to deliver queued mail. This
check is performed automatically if no client-hosts
are specified.-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 VARIABLES No environment variables are used. However, at systemstart-up, svc:/network/smtp:sendmail reads
/etc/default/sendmail. In this file, if the variableETRN_HOSTS is set, svc:/network/smtp:sendmail parses this
variable and invokes etrn appropriately. ETRN_HOSTS should
be of the form:SunOS 5.11 Last change: 10 Aug 2004 1
System Administration Commands etrn(1M)
"s1:c1.1,c1.2 s2:c2.1 s3:c3.1,c3.2,c3.3"That is, white-space separated groups of server:client where
client can be one or more comma-separated names. The :client
part is optional. server is the name of the server to prod; a mail queue run is requested for each client name. This is comparable to running:/usr/lib/sendmail -qR client
on the host server.EXAMPLES
Example 1 Using etrn
Inserting the line:ETRN_HOSTS="s1.domain.com:clnt.domain.com s2.domain.com:clnt.domain.com"
in /etc/default/sendmail results insvc:/network/smtp:sendmail invoking etrn such that ETRN com-
mands are sent to both s1.domain.com and s2.domain.com, with both having clnt.domain.com as the ETRN argument. The line:ETRN_HOSTS="server.domain.com:client1.domain.com,client2.domain.com"
results in two ETRN commands being sent to server.domain.com, one with the argument client1.domain.com, the other with the argument client2.domain.com.SunOS 5.11 Last change: 10 Aug 2004 2
System Administration Commands etrn(1M)
The line:ETRN_HOSTS="server1.domain.com server2.domain.com"
results in set of a ETRN commands being sent to both server1.domain.com and server2.domain.com; each set contains one ETRN command for each host name for which sendmail(1M) accepts email, with that host name as the argument. FILES /etc/mail/sendmail.cf sendmail configuration file /etc/default/sendmail Variables used by svc:/network/smtp:sendmailATTRIBUTES
See attributes(5) for descriptions of the following attri-
butes:_____________________________________________________________
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
|_____________________________|______________________________|
| Availability | service/network/smtp/sendmail||_____________________________|______________________________|
| Interface Stability | Committed ||_____________________________|______________________________|
SEE ALSO
sendmail(1M), attributes(5) RFC 1985 NOTES Not all SMTP servers support ETRN.SunOS 5.11 Last change: 10 Aug 2004 3