Sendmail - relay Host unknown since adding dns

UNIX HP-UX
1

Hi
ever since we�ve added the server in DNS, sendmail stopped working, but everything seems to be configured properly although in the mail logs we see:

Jul 10 16:52:58 itc01 sendmail[5593]: t6AEqrHT005593: from=root, size=6, class=0, nrcpts=1, msgid=<201507101452.t6AEqrHT005593@itc01.headquarter.tmm>, relay=root@localhost
Jul 10 16:53:08 itc01 sendmail[5593]: t6AEqrHT005593: to=myname@dominio.co.yy, ctladdr=root (0/3), delay=00:00:15, xdelay=00:00:10, mailer=relay, pri=30006, relay=192.168.1.39, dsn=5.1.2, stat=Host unknown (Name server: 192.168.1.39: host not found)
itc01[320]/etc/mail #

but in /etc/hosts file I have:

192.168.1.39    exchange-hub.headquarter.tmm

the

/etc/resolv.conf

is:

more /etc/resolv.conf
domain dominio.co.yy
nameserver 192.168.1.69
nameserver 192.168.1.39
search headquarter.tmm

and the

/etc/nsswitch.conf

:

passwd:       compat
group:        compat
hosts:        files dns
ipnodes:      dns [NOTFOUND=return] nis [NOTFOUND=return] files
networks:     nis [NOTFOUND=return] files
protocols:    nis [NOTFOUND=return] files
rpc:          nis [NOTFOUND=return] files
publickey:    nis [NOTFOUND=return] files
netgroup:     nis [NOTFOUND=return] files
automount:    files nis
#aliases:      files nis
aliases:      files
services:     nis [NOTFOUND=return] files

Please can you help?

---------- Post updated at 05:23 PM ---------- Previous update was at 05:07 PM ----------

problem solved , I have put the FQDN of the server DS macro of

sendmail.cf
2 
host 192.168.1.39

and

getent hosts 192.168.1.39

should give the same hostname.
getent (if available on your system) uses the libc defaults that is normally /etc/nsswitch.conf, eventually through a nscd cache.

For ipnodes (Solaris?) I recommend only "files". In few configurations "files dns" can make sense, but always "files" first, and "localhost" should be in /etc/hosts file.
(Not relevant here: also services should be "files" first, for performance reason.)
Do you have nscd with hosts caching (and ipnodes caching) enabled? (See /etc/nscd.conf and command nscd -g ) Then restart nscd.

3

Are we actually discussing this thread again?

Robin

4

:wink:
Now I see, it is HP-UX. Does not have nscd, and no getent.
My /etc/nsswitch.conf recommendations are valid nevertheless.
While I wonder what HP-UX does with ipnodes...it looks like this line was blindly copied from the Sun/Solaris nsswitch.conf and does not have an effect.
--
DS in sendmail.cf is the valid line to set the relayhost.
Normally sendmail does

nslookup -q=mx relayhost

and if not successful

nslookup -q=a relayhost

or

nslookup -q=aaaa relayhost