Solaris

...hm, but what is trying to make the smtp connection in the first place?

If it's sol10, sendmail likes to talk to itself. It's generally better to tell it to bind to localhost:25 only than to actually disable it altogether.

mutter, mutter, grumble, mutter.......

Hi Smiling Dragon,

I am new to UNIX....can you teach me the step on how to go about binding port 25 to localhost? Does it have any impact?

in addition to the below question,

recently, i noticed that i have a statement in /var/adm/messages. Does anybody know what it actually mean and how do i solve it?

sysec 13 14:05:36 xxxxxx sshd2[10921]: [ID 702911 auth.warning] WARNING: DNS lookup failed for "10.10.42.154".

Most daemons (like sendmail) will automatically listen on every network interface they find on whatever port (in this case 25). By binding to localhost (127.0.0.1) only, you restrict access to only the local machine. That way, local processes that need sendmail to send messages etc can still get at it, but other servers and clients can't connect across the network.

So the impact would be very similar to stopping the sendmail service altogether except that it will also allow outgoing mail to work with a full queueing and automatic resend etc.

eg:

Code:

# uname -a
SunOS server1 5.10 Generic_118833-36 sun4v sparc SUNW,Sun-Fire-T200
# ps -ef | grep sendmail
   smmsp   558     1   0   Nov 01 ?           0:16 /usr/lib/sendmail -Ac -q15m
    root   559     1   0   Nov 01 ?           2:11 /usr/lib/sendmail -bd -q15m
# telnet server1 25
Trying xxx.xxx.xxx.xxx...
telnet: Unable to connect to remote host: Connection refused
# telnet localhost 25
Trying 127.0.0.1...
Connected to localhost.
Escape character is '^]'.
220 server1 ESMTP Sendmail...

If you add a DAEMON_OPTION of "Addr=127.0.0.1" to your m4 config and recreate the cf from that. Should do the trick.

We use:

Code:

DAEMON_OPTIONS(`Name=Name=NoMTA4, Family=inet, Addr=127.0.0.1')

This is sshd warning you that it was unable to find a DNS reverse lookup for an incomming connection from 10.10.42.154. In otherwords, it can't identify what machine that is. You'll probably find that if you do a 'who' command, it will list the IP rather than hostname for that connection.

If you add a DAEMON_OPTION of "Addr=127.0.0.1" to your m4 config and recreate the cf from that. Should do the trick.

We use:

Code:

DAEMON_OPTIONS(`Name=Name=NoMTA4, Family=inet, Addr=127.0.0.1')

Hi,

Can you advice me which file should i modify for the above code? Many thanks

sendmail when disabled as a daemon is quite unlikely to talk to itself.

I suspect cron or a similar program is trying to send a mail to root or another user about some issue running a crontab command.