Path: utzoo!utgpu!watserv1!watmath!att!att!emory!wuarchive!zaphod.mps.ohio-state.edu!rpi!batcomputer!munnari.oz.au!metro!usage.csd.unsw.oz.au!syacus!grants
From: grants@syacus.acus.oz (Grant Sayer)
Newsgroups: comp.mail.sendmail
Subject: Host Name Lookup Failure in testmode
Keywords: sendmail configuration, testing, setup
Message-ID: <1195@syacus.acus.oz>
Date: 20 Nov 90 05:47:44 GMT
Organization: Australian Centre for Unisys Software, Sydney
Lines: 23

With testing a connection between two machines (host1 and host2)
using 'sendmail -v user@host1 < /dev/null' the SMTP connection works
one way and not the other.  For example, 
	1. sendmail -v user@host2 < dev/null  (from host1)
		- results in mail transferred and normal 250 greeting messages

	2. sendmail -v user@host1 < /dev/null (from host2)
		- results in error message
		user@host1: Deferred Host name lookup failure.

The sendmails are running on SysV with BSD support for TCP/IP and similar
sendmail.cf files.  Each sendmail was invoked as 'sendmail -bd -q20m'.

From examining some sendmail source (sendmail5.64) it appears that the 
errors are from daemon.c, printed using err.c after failure to resolve
the host name (i.e error state is TRY_AGAIN+MAX_RETRIES)

Any suggestions as to why the problem is only one-way ?

Thanks In Advance
Grant Sayer                   ACSnet : grants@syacus.acus.oz
Ph : +61 2 887-6810         Internet : grants@syacus.acus.OZ.AU
Fax: +61 2 888-2424             UUCP : uunet!munnari!syacus.acus.oz.au!grants