Configuration Guide

Wondering what to expect when you sign up? We’ve laid it all out here for you.

You can also download a standalone version here.

Configuration Steps
Prepare Your Configuration
Extra Tips

Configuration Steps

Configuration is fully automated. Here’s what to expect:

Cumulus access
Direct clients and partners will get login credentials to our client management interface. You can start by personalizing Contact Persons and by adding your other domains.
Server testing
Our systems will check your servers to make sure there won’t be any unexpected problems. If a problem is detected, we will notify you.
DNS Records
Five minutes after server testing is completed successfully, you will receive instructions regarding MX record changes in your DNS zone.
2 hours after changing your MX records, an email will confirm that service is now active.
Server and firewall optimization
2 hours after we confirm service activation, we will send instructions to help optimize your setup:
  • Restrict SMTP access to only our filters.
  • Disable built-in verifications that can cause False Positives.

Trial Duration

Your free trial will end 30 days after it is requested. To make the best use of your free trial period, please change your domain's MX records as soon as you receive our instructions.


The service is active once all your MX records point to our filters. Make sure that only our MX records are used. Having any other MX records means you aren't fully protected

Prepare Your Configuration

Here are some things you can do to prepare your configuration. They fall into three categories:

  • Essential: These are absolutely essential for configuration and are necessary for the service to work.
  • Important: These are important. Doing these will ensure a smooth startup with no surprises.
  • Optimal: These can be configured once the solution is implemented to improve your experience and security.


Confirm service compatibility

Most servers are compatible. Check just to make sure.

Decide which service you will need

Inbound & outbound Filtering or only Inbound Filtering.

Collect information

  • List of domains that will be added to the service
    • Needed to configure the service.
  • Mail server address (IP or Hostname) for each domain.
    • Needed to configure the service.
  • How many users use each domain?


Collect information

  • List of devices or services that send emails directly to your mail server (eg.: printers, scanners, faxes, VOIP systems, etc.).
    • Can be used for allow list customization and service streamlining
  • List of clients, partners, or suppliers that are critical to your operations.
    • Can be used for allow list customization and service streamlining

Decide who will be given access to the Cumulus client portal

There are three types of accounts: Administrators, Quarantine Administrators, and Users. Learn more.

Decide who will receive communications from Cumulus and set their subject preferences

The first administrator is created as Default contact person. Learn more.

Decide on a quarantine management strategy

Managed by administrators only, users only, or a combination of both. Learn more.


Decide on problem message reporting strategy

You can deploy the M 365 Add-In, install an Outlook plugin or report messages manually. Learn more.

Decide which names to add to the Spearphishing Module

Block BEC and spearphishing using only a person's name. Learn more.

Decide whether to setup LDAP synchronization

Allow Cumulus to leverage user information in your AD via LDAP synchronization. Learn more.

Decide whether to activate 2FA and on which accounts

Secure user and admin accounts with 2FA. Learn more.

Extra Tips

Subscribe to Our Status Page

To be informed automatically of all changes to the status of our systems, please sign up to our Statuspage.

Prep Your Server and MX Records

Make sure to allow all of our IP ranges in your firewall. Deactivate any SPF checks performed by your server on incoming emails. 

We suggest that you lower the TTL on your MX records to a value of 7200 (2 hours) or less. Reducing the TTL ahead of any DNS changes will help streamline the activation process and cut down on the time it takes for the service to be fully active.

Service will remain inactive until these changes have been completed. Changing your MX records will not cause any email downtime or modify how your users are receiving their emails.

How to Change Your MX Records

We can't provide any precise steps to change your MX records since each DNS-management interface has its particularities. 

  • If you have access to a control panel that enables you to perform these changes yourself, please use it to change the MX records. 
  • If you don't have access to the DNS zone for this domain, please forward these instructions to your DNS service provider or to your email hosting provider. 

We recommend copy/pasting the MX records from your MX change instructions in order to avoid mistakes.

All your MX records must point to our filters in order for the service to be considered active.

When to Change Your MX Records

Changing your MX records is necessary to activate the service. It's best to do this step as soon as possible in order to make the most of your Free Trial.

There is no risk of downtime to changing your MX records during operating hours. In fact, we believe it is better to change them during operating hours. 

If you have any questions or encounter a problem, our technical team is quickly available to help you. Also, there will be no interruption to email-flow.

How Long Before the Service is Active?

This depends on the TTL set for your MX records. The longer the TTL, the more time it will take before all your emails are 100% filtered by our service. We recommend you reduce your MX record TTL to 7200 (2 hours) or less in order to speed up the migration. 

Our servers perform periodic verifications of your domain's MX records. When we detect that the MX records have changed, you will receive an email confirming activation.