--- layout: handbook-page-toc title: Real Time Blacklist Delisting category: GitLab.com --- ## On this page {:.no_toc .hidden-md .hidden-lg} - TOC {:toc .hidden-md .hidden-lg} ### Overview In some rare cases, you may need to reach out to Mailgun support to remove our IP addresses from a Real-time Blacklist (RBL). This workflow will cover how to verify and resolve these issues. ### Check for Supression in Mailgun If a customer is reporting that they are not receiving a confirmation email, you'll want to go through the [confirmation email](https://about.gitlab.com/handbook/support/workflows/confirmation_emails.html) workflow first. When in the Mailgun panel, [check for a supression](https://about.gitlab.com/handbook/support/workflows/confirmation_emails.html#check-mailgun). ### Verify the RBL listing In the logs, if you see a mention of a rejection due to abuse or explicit confirmation of a blacklist, proceed to the link and look up the IP address. Every provider will be different, but if a lookup database is available, you should verify that it is listed and if a reason is stated. ``` "delivery-status": { "tls": true, "mx-host": "mx1.external-mailserver.com", "attempt-no": 1, "description": "", "session-seconds": 1.7985761165618896, "code": 550, "message": "5.7.1 H:M11 [192.237.158.143] Connection refused due to abuse. Please see http://mailspike.org/iplookup.html or contact your E-mail provider." ``` You can confirm that the IP address is ours by doing a "host" lookup on the IP address. It should always end in `mg.gitlab.com`. ``` > host 192.237.158.143 143.158.237.192.in-addr.arpa domain name pointer do158-143.mg.gitlab.com. ``` ### Open a Ticket With Mailgun Navigate to Mailgun > [Support](https://app.mailgun.com/app/support) and click "Create Ticket". Be sure to include: 1. The IP Address that is blacklisted 1. The name of the RBL and link to it (Found in the Message returned by the mail server) 1. Copy of the Logs ### Follow up Be sure to follow up with the customer and let them know that we've requested support through Mailgun. They should return a response within 24 hours. If we are blacklisted due to a specific account, please check in with Site Reliability Engineers in #production.