I am setting up Nagios on an Ubuntu 8.10 server and am unable to get email notifications to work. I don't think Nagios is the problem since I cannot get the following simple line to send an email:
mail -s "Test Email" email@example.com
where firstname.lastname@example.org is my real email address. I've tried sending to both an internal and an external address. I installed mailx prior to this testing and it installed successfully. In other posts, it said to troubleshoot by checking mail.log which I found in /etc/log but this file is empty. What else can I do to troubleshoot mail? Thanks.