Troubleshooting Email Loops from Mail Security Gateways

Issue

NinjaOne Ticketing repeatedly creates new tickets after a network-attached appliance or automated system sends it an email notification. The new tickets come from delivery failure notices and other automated messages, and they continue to appear in a loop.

This issue affects senders that cannot receive or process replies. Examples include Automatic Call Distribution (ACD) telephony systems, Uninterruptible Power Supply (UPS) devices, and network monitoring systems.

Environment

NinjaOne Ticketing

Cause

Network-attached appliances and automated systems send email but are not configured to receive or process replies. When NinjaOne Ticketing receives an inbound email from one of these senders, it creates a ticket. It may then send an automated acknowledgment to the originating address.

The sender cannot process the acknowledgment, so it responds with a delivery failure notice or another automated message. NinjaOne Ticketing receives that message, creates another ticket, and sends another acknowledgment, which continues the loop.

Resolution

Complete the following three steps in order to allow inbound emails from the appliance or system to create tickets without triggering the loop.

Step 1: Allowlist the Sender

Allowlisting the sender's address or domain ensures that inbound emails from the appliance or system create tickets automatically without manual approval. To add the sender to the allowlist, perform the following steps:

1. In NinjaOne, navigate to Administration → Apps → NinjaOne Ticketing.
2. Click the Email tab, select Allowlist from the drop-down menu, and then click Add.
3. Select Domain or Email from the Type drop-down menu.
4. Enter the sender's domain name or full email address.
5. Click Save.

Step 2: Add or Verify a Notification Rule

A notification rule prevents NinjaOne Ticketing from sending automated emails to a specific address pattern. NinjaOne Ticketing includes default notification rules for common automated addresses, such as noreply@* and mailer-daemon@*. To verify or add a rule for the sender, perform the following steps:

1. Navigate to Administration → Apps → NinjaOne Ticketing, and then open the Email → Notification Rules tab.
2. Review the existing rules, including the default rules, for a rule that matches the sender's address pattern.
3. Click Add to create a rule for the sender's address or domain pattern when no existing rule matches it.
4. Enter the sender's address or domain pattern in the Rule pattern field.
5. Complete the remaining fields, and then click Update. For field descriptions, refer to the Notification Rules section of NinjaOne Ticketing: Email and Notification Management.

Step 3: Set the System Email Notification to None

Setting the Requester when ticket is created via email notification to None for the applicable user type prevents NinjaOne Ticketing from generating the acknowledgment, regardless of any notification rule. To change the setting, perform the following steps:

1. Navigate to Administration → Apps → NinjaOne Ticketing, and then click the General tab.
2. In the System email notifications section, click Edit.
3. In the System email notifications dialog, locate Requester when ticket is created via email for the applicable user type, either Technicians or End users/contacts.
4. Set the notification to None, and then save the change.

Additional Resources

To learn more about configuring email and notification settings in NinjaOne Ticketing, refer to NinjaOne Ticketing: Email and Notification Management.