On 5/15/2012 4:57 PM, Bowie Bailey wrote:
On 5/15/2012 4:48 PM, Jussi Hirvi wrote:
On 15.5.2012 23.22, Alexander Dalloz wrote:
It is technically impossible that the telnet to target port 25 succeeds from the same system on which the Sendmail gets a connection refused, unless Sendmail is configured to use a non-standard target port.
That is why I am baffled. :-/
I could use a way to see what port sendmail is actually using to make the contact. My assumption is that when the log entry (see my orig post) says "mailer=esmtp,", it implies port 25 - but then it really does not make sense that the connection is refused.
On the primary mail server (which I try in vain to contact) I see *nothing* about the failed connections in the maillog, even though I raised log_level to 19.
You could use wireshark to monitor the network traffic and determine exactly what happens when sendmail tries to make the connection.
A couple of things to check. I don't know if these servers are in the same location or not but it is possible if not, that your provider blocks port 25. Here are two configs to check.
dnl # The following causes sendmail to only listen on the IPv4 loopback address dnl # 127.0.0.1 and not on any other network devices. Remove the loopback dnl # address restriction to accept email from the internet or intranet. dnl # DAEMON_OPTIONS(`Port=smtp, Name=MTA')dnl
If this is not done on the primary, it will not listen to anything but itself.... so the backup wouldn't be able to contact it.
dnl # dnl # The following causes sendmail to additionally listen to port 587 for dnl # mail from MUAs that authenticate. Roaming users who can't reach their dnl # preferred sendmail daemon due to port 25 being blocked or redirected find dnl # this useful. dnl # DAEMON_OPTIONS(`Port=submission, Name=MSA, M=Ea')dnl
and this if it is possible that port 25 is blocked.
Sorry if this has already been discussed. I stepped in late on the conversation.