Troubleshoot Unitrends Backup System failure to send email notifications.
Email notifications are never received by specified recipient.
SMTP traffic blocked by environment:
Many network firewalls and internet service providers block or filter outgoing traffic on the default SMTP port, 25, in order to prevent the sending of unsolicited bulk email, or spam, from their networks. This prevents the Unitrends Backup System from successfully sending email notifications.
Gmail will not relay mail via port 25, thus attempts to send mail via the default configuration will fail.
Gmail requires authentication, and the account used must have both "Less Secure Apps" turned ON and 2-Step Authentication turned OFF. Authentication will fail otherwise.
Gapps, or Google Apps, has unique requirements in comparison to Gmail. Please use Gmail, not Gapps, for relay from Unitrends devices.
Top-level domain alias in /etc/hosts:
Often, customers will mistakenly enter their toplevel domain name in the Fully Qualified Host Name field under Settings / Clients, Networing, & Notifications / Networks / Hostname.
This creates an alias in the /etc/hosts file pointing their domain name to the IP address of the Backup System. Consequently, the Backup System sends all mail for given domain to itself, and usually fails with the error “User uknown.”
Sendmail doesn't support certain special characters: Pound/Hash #, Equals-sign =, and colon : are not supported characters and will result in bad username and password errors when testing email transport.
SMTP traffic blocked by environment AND Gmail
Configure the Unitrends Backup System to relay mail through an external SMTP server via the submission port, which is port 587.
To configure the SMTP server, do the following:
In the Unitrends Backup System user interface,
Go to Configure > Appliances, edit appliance and Email tab.
Fill in SMTP server.
If necessary ( it is for Gmail ), check the box next to SMTP Server Authentication Required
If authentication is required, fill in the username and password fields
Fill in the Test Email Address field
In the console/shell of the Backup System:
Connect to your appliance through the console (Press Alt+F2 to access the command line) or via SSH using PuTTY or another utility to SSH to your appliance's IP address through port 22. You will need to know the root OS password which can be reset via console access.
Locate the following line:
Note: smtp.gmail.com will be replaced with the SMTP server you specified above.
Insert the following two lines AFTER the SMART_HOST line above:
define(`RELAY_MAILER_ARGS', `TCP $h 587')dnl
define(`ESMTP_MAILER_ARGS', `TCP $h 587')dnl
Save the file
Issue the following command at the shell prompt
m4 /usr/share/sendmail-cf/m4/cf.m4 /etc/mail/sendmail.mc > /etc/mail/sendmail.cf
service sendmail restart
Domain alias in /etc/hosts
Login to the Backup System user interface, and go to Clients, Networks, and Notifications.
Click on Networks, then Hostname.
Change the Fully Qualified Hostname entry to a fully hostname, ie. backup.domain.com, instead of just domain.com.
Go up one level in the UI menu to Networks, and click on Hosts. Remove any host aliases for domain.com.
Test Email Transport
Connect to your appliance through the console (Press Alt+F2 to access the command line) or via SSH using PuTTY or another utility to SSH to your appliance's IP address through port 22. You will need to know the root OS password which can be reset via console access
From the command line, send a test message to yourself, ie.
echo Subject: test; echo; echo test|/usr/sbin/sendmail -Am -i -v email@example.com
This command will "walk" the SMTP process and will report any failures in the output (DNS resolution failures, authentication failures, etc). If the message sends successfully, at the end you will see "Message queued for delivery" or in some cases OK SENT (depends on the type of server doing the relay).
You can also tail the maillog:
tail -f /var/log/maillog
Hit CTRL-c to exit tail.
If you reboot the system and the mail will not flow need to check that the service is set to start on boot.
chkconfig --list |grep sendmail
sendmail 0:off 1:off 2:off 3:off 4:off 5:off 6:off
[root@Unitrends-Hampton log]# chkconfig sendmail on
[root@Unitrends-Hampton log]# chkconfig --list |grep sendmail
sendmail 0:off 1:off 2:on 3:on 4:on 5:on 6:off
Google may require the account to be "unlocked" in order to do this the customer will need to visit: http://www.google.com/accounts/DisplayUnlockCaptcha
Also see https://support.google.com/mail/answer/14257 for more information on Gmail account issues.