IT & Engineering

Reliable Linux server alerts with Mailgun

This post was written and contributed by Major Hayden, Principal Architect at Rackspace. Today’s multi-cloud world allows for lots of flexibility, but infrastructure sprawl creates serious challenges for email delivery. Mailgun customers already know how it can help them send critical business emails, such as receipts, newsletters, and promotions. What about all of those other emails that servers need to send when something goes wrong?

PUBLISHED ON

PUBLISHED ON

This post was written and contributed by Major Hayden, Principal Architect at Rackspace.

Today’s multi-cloud world allows for lots of flexibility, but infrastructure sprawl creates serious challenges for email delivery. Mailgun customers already know how it can help them send critical business emails, such as receipts, newsletters, and promotions. What about all of those other emails that servers need to send when something goes wrong?

Servers often need to send out an alert via email when something goes wrong or when an administrator needs to be aware of a change. For example, most cron job failures end up creating emails that are shipped to someone on the system. These emails often fall into the root user’s mailbox.

For some servers, root‘s mailbox is a black hole because the account isn’t configured to forward email elsewhere. For others, a system administrator might configure another address to receive the root user’s email. Getting that email delivered outside the server is challenging in cloud environments for many reasons:

  • Many IP addresses on cloud platforms are already in email blacklists 

  • Reverse DNS isn't always configured correctly by administrators in cloud environments

  • Maintaining SPF records for constantly fluctuating environments is difficult

  • Distributing DomainKeys configurations reliably is also difficult

  • Some alert emails may be dropped into spam folders due to their content, despite getting everything right in the mail server configuration

  • Some cloud providers block outbound connections on common SMTP ports (like 25, 465, and 587)

Mailgun can deliver these important emails reliably on almost every system with internet access. Common MTA’s like postfix or sendmail can connect to Mailgun’s SMTP Relay service and send email with very little configuration. In addition, all of that email can be delivered securely with SSL/TLS.

I’ve made this process a little easier by creating an Ansible role called ansible-mailgun that will install postfix and configure it to use Mailgun as an SMTP relay. The role can be easily added to any existing Ansible playbook:

There are only three variables to configure for the role to work. First, the mailgunusername and mailgunpassword appear in the Mailgun dashboard for each domain under the Domain Information heading. The rootforward_ variable should be set to an email address that can receive the email for the root user on each server.

Here’s how it works when an alert email is generated on one of the servers with the ansible_mailgun role applied:

  1. The alert email is dropped into the postfix’s delivery queue for root

  2. Postfix connects to Mailgun via SMTP to forward the email (the address configured as rootforward_ in the Ansible role)

  3. Mailgun delivers the email to the user who is configured to receive root‘s email

This mail delivery path ensures that your alerts are delivered reliably, no matter where they’re generated.

Sign Up

It's easy to get started. And it's free.

See what you can accomplish with the world’s best email delivery platform.

Related readings

A practical guide to using Mailgun’s webhooks

Transactional emails are essential for most apps. We send welcome emails, password...

Read more

Best practices for successful email delivery

Composing good email is important but making sure it successfully reaches your recipients is critical. So many well-intended messages end up in spam (60% in a recent analysis)...

Read more

Force for change: It's time to speak out

There are moments when it becomes necessary to speak out and come together as a force ...

Read more

Popular posts

Two men talking about email authentication

Build Laravel 10 email authentication with Mailgun and Digital Ocean

When it was first released, Laravel version 5.7 added a new capability to verify user’s emails. If you’ve ever run php artisan make:auth within a Laravel app you’ll know the...

Read more

Gods with gears in city street

Sending email using the Mailgun PHP API

It’s been a while since the Mailgun PHP SDK came around, and we’ve seen lots of changes: new functionalities, new integrations built on top, new API endpoints…yet the core of PHP...

Read more

God with mask on chair

Here’s everything you need to know about DNS blocklists

The word “blocklist” can almost seem like something out of a movie – a little dramatic, silly, and a little unreal. Unfortunately, in the real world, blocklists are definitely something you...

Read more

See what you can accomplish with the world's best email delivery platform. It's easy to get started.Let's get sending
CTA icon