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  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 options are supported:

     -b    System boot  special  case.  Make  sure  localhost  is
           accepting  SMTP connections before initiating the SMTP
           session with server-host.

           This option is useful because it prevents race  condi-
           tions  between  sendmail(1M) accepting connections and
           server-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  system
     start-up,          svc:/network/smtp:sendmail          reads
     /etc/default/sendmail.  In  this  file,  if   the   variable
     ETRNHOSTS  is  set,  svc:/network/smtp:sendmail parses this
     variable and invokes etrn appropriately.  ETRNHOSTS  should
     be of the form:




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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:


       ETRNHOSTS="s1.domain.com:clnt.domain.com s2.domain.com:clnt.domain.com"




     in         /etc/default/sendmail         results          in
     svc:/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:


       ETRNHOSTS="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.







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System Administration Commands                           etrn(1M)



     The line:


       ETRNHOSTS="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:sendmail


ATRIBUTES
     See attributes(5) for descriptions of the  following  attri-
     butes:



     
           ATRIBUTE TYPE               ATRIBUTE VALUE       
    
     Availability                 SUNWsndmu                   
    
     Interface Stability          Stable                      
    


SEE ALSO
     sendmail(1M), attributes(5)


     RFC 1985

NOTES
     Not all SMTP servers support ETRN.










SunOS 5.11          Last change: 10 Aug 2004                    3