Postfix Configuration and troubleshooting woes

[omegahalo-Re5JQEeQqe8AvxtiuMwx3w at public.gmane.org (Chris O'Connell)]

Greetings All,


 I'm installing a Nagios server in my office to monitor some network
devices. I have an exchange server, but ideally I will configure my Nagios
box to send emails directly by using an MX record.


 To begin with, I'm trying to just get Postfix to work on a local level, so
I can send messages back and forth to users on my local machine.


 I'm having some Postfix trouble. I've never installed Postfix before and
have no experience configuring it. I've followed the instructions to install
the packages. Here's what I've done to try to test it:


 nagios at nagios:/usr/local/nagios/etc$ netcat localhost 25

220 nagios ESMTP Postfix (Ubuntu)

ehlo localhost

250-nagios

250-PIPELINING

250-SIZE 10240000

250-VRFY

250-ETRN

250-STARTTLS

250-ENHANCEDSTATUSCODES

250-8BITMIME

250 DSN

mail from: root at localhost

250 2.1.0 Ok

rcpt to: nagios at localhost

250 2.1.5 Ok

data

354 End data with <CR><LF>.<CR><LF>

Subject: Test email!

testing 123!

.

250 2.0.0 Ok: queued as B826361DC7

quit

221 2.0.0 Bye


 Now, when I switch to the nagios user and type mail I am told there is no
new mail. When I navigate to my /home/nagios/Maildir/new I see a new message
in there with the appropriate time stamp, but the message never gets
delivered.


 Any thoughts on this?


 # See /usr/share/postfix/main.cf.dist for a commented, more complete
version

  # Debian specific: Specifying a file name will cause the first

# line of that file to be used as the name. The Debian default

# is /etc/mailname.

#myorigin = /etc/mailname

 smtpd_banner = $myhostname ESMTP $mail_name (Ubuntu)

biff = no

 # appending .domain is the MUA's job.

append_dot_mydomain = no

 # Uncomment the next line to generate "delayed mail" warnings

#delay_warning_time = 4h

 readme_directory = no

 # TLS parameters

smtpd_tls_cert_file=/etc/ssl/certs/ssl-cert-snakeoil.pem

smtpd_tls_key_file=/etc/ssl/private/ssl-cert-snakeoil.key

smtpd_use_tls=yes

smtpd_tls_session_cache_database = btree:${data_directory}/smtpd_scache

smtp_tls_session_cache_database = btree:${data_directory}/smtp_scache

 # See /usr/share/doc/postfix/TLS_README.gz in the postfix-doc package for

# information on enabling SSL in the smtp client.

 myhostname = nagios

alias_maps = hash:/etc/aliases

alias_database = hash:/etc/aliases

myorigin = /etc/mailname

mydestination = sjnen.org, nagios, localhost.localdomain, localhost

relayhost = 192.168.1.12

mailbox_size_limit = 0

recipient_delimiter = +

inet_interfaces = all

home_mailbox = Maildir/

mailbox_command =

inet_protocols = all

mynetworks = 127.0.0.0/8, 192.168.1.0/24

default_transport = smtp

relay_transport = smtp