Following are some MTA candidates for nodes
nullmailer
Nullmailer is a replacement MTA for hosts, which relay to a fixed set of smart relays. It is designed to be simple to configure and especially useful on slave machines and in chroots. The sendmail interface of this package doesn't provide the -bs switch, hence it's not LSB compatible!
ssmtp
A secure, effective and simple extremely MTA to get mail off a system to your mail hub. It contains no suid-binaries or other dangerous things - no mail spool to poke around in, and no daemons running in the background. Mail is simply forwarded to the configured mailhost. Extremely easy configuration. It does not receive mail, expand aliases or manage a queue. That belongs on a mail hub with a system administrator.
esmtp
It is a user configurable relay-only Mail Transfer Agent (MTA) with a sendmail-compatible syntax. It's based on libESMTP supporting the AUTH (including the CRAM-MD5 and NTLM SASL mechanisms) and the
StartTLS SMTP extensions.ESMTP does not receive mail, expand aliases or manage a queue but can deliver mail locally via an MDA.
nbsmtp
It is a simple MTA to send your mails to another mail server via SMTP. It is used when you don't want a big MTA on your box. Reasons are maybe if you want to relay your mail over the one of your provider or you have a powerful mail server in your company which manages the queue. This means that nbsmtp does not manage your local mail queue, it does only send it to a hub. To use nbsmtp you will also need an account on a SMTP-server which allows you to relay over it.
There are version for lenny(testing) and sid(unstable).
Test
ssmtp: It is installed and running on Node35. The configuration is very simple, just put the right mailhub's address (at the moment, it is Node43's IP address) in the /etc/ssmtp/ssmtp.conf file . Logcheck is able to send report email from Node35 to Node43.
ssmtp configuration for computer nodes
ssmtp is chosen for computer nodes on the cluster. set the configuration file /etc/ssmtp/ssmtp.conf as followings:
Note: Change the mailhub address when the environment changed.
# The person who gets all mail for userids < 1000
# Make this empty to disable rewriting.
# mail to root@ will goes to postmaster@
root=postmaster
# The place where the mail goes. The actual machine name is required no
# MX records are consulted. Commonly mailhosts are named mail.domain.com
mailhub=192.168.0.43
# Where will the mail seem to come from?
# rewriteDomain=
# The full hostname
# hostname=node35.
# Are users allowed to set their own From: address?
# YES - Allow the user to specify their own From: address
# NO - Use the system generated From: address
FromLineOverride=YES