Creating and configuring an email domain is a required part of providing email functionality within some of the Hornbill applications. The domain is primarily concerned with facilitating the outbound mail operation, delivering from the Hornbill instance to the outside world.

Topics Covered

• Creating a new email domain.
• Enabling DKIM.
• Choosing a routing mode.
• Performing an SPF test.

Before You Begin

This guide takes you through administrative configurations. The following will be needed to complete this guide:

• Hornbill Admin User access.
• General knowledge of using Configuration.
• A fully qualified domain name for outgoing email.
• A working knowledge of your mail servers and firewalls within your organization.

Creating an Email Domain

To create and configure a new email domain in Configuration.

1. Search Configuration for Email Domain.
2. In the results, select Email Domain.
3. Click on the + Add Outbound Route button.

Details

• Domain Name
  The name that is used here must be a valid domain name. For example ‘mycompany.com’.
• Enable processing of incoming mail on this route
  Turning this on will allow any email that has been sent to this domain to be processed by the SMTP service and allow it to be routed to the appropriate mailbox.
• Automatically create an address for this route when a new mailbox is created
  When a new user is created a personal mailbox is created and associated with that user. When this feature is enabled, each new user will be automatically allocated an email address using this domain name. The Address Format can then be used to set the format of the username.
• Address Format
  The Address Format is to be used when a new personal mailbox is created. This is only available if you have enabled the option above to automatically create addresses for this route. The formats that can be selected are based on variations of the Firstname and Lastname of the user with the exception of the LoginID.

Enable DKIM

DomainKeys Identified Mail (DKIM) is an email authentication method designed to make sure messages aren’t altered in transit between the sending and recipient servers and to detect forged sender addresses in email (email spoofing), a technique often used in phishing and email spam.

• DKIM Selector
  A DKIM selector is specified when the private/public key pair is created when DKIM is set up for the email domain (or email sender), and it can be any arbitrary string of text.
• DKIM Key Size
  Choose between 1024 and 2048 bits for your key size.

Outbound Routing Mode

There are two methods of outbound routing available in Hornbill. Select the one that is most desirable to you based on the descriptions below.

Option 1: DNS Routing

If you wish to use DNS Routing, this requires the following steps.

1. Add an SPF and TXT record to your DNS server.
2. Validating the record using the Test SPF button.
3. After a successful test, click on the Create Route button.

When an email is delivered, our servers will automatically negotiate the highest level of transport encryption supported by the remote SMTP server. This is completely automatic and is negotiated every time a new SMTP connection is made. We support the TLS 1.2, TLS 1.1, TLS 1.0, SSL 3.0, and Plain Text protocols, prioritized and negotiated for in that order. The SPF/TXT record allows Hornbill to send emails using the configured domain without the risk of breaching any anti-spam/email source validation checks.

Option 2: SMTP SmartHost

A smart host is a type of email message transfer agent that allows a Simple Mail Transfer Protocol (SMTP) server to route email via an intermediate e-mail server rather than directly to the recipient’s server. With this method, an e-mail server within your organization is configured to allow the relaying of emails from your Hornbill instance (based in our data center) to your end users. With the relay configured, any outbound email will pass through your domain, and therefore, from the recipient’s perspective, the source domain will correspond to that used in the “from address” that we configure within Hornbill.

To successfully complete the email integration using this method you will need to:

1. Create an outbound route in Hornbill and configure the necessary details.
2. Configure a relay connector on your mail server (allowing relay from the appropriate origin IP stated below).
3. Configure any necessary firewall rules (allowing traffic from the appropriate origin IP) to allow communication from your Hornbill instance.

Firewall - Origin IP Address

The origin IP that should be specified in any such firewall rules is one of the following and is dependent on the location of your instance. You should have both the Primary and Secondary IP for your geographical area:

• Europe
  87.117.243.10 or 212.71.225.67
  If you are a UK or European customer, your instance will be located in our European data center and any outbound mail will originate from these IP addresses.
• North America
  69.174.249.200 or 64.34.188.200
  If you are a North American customer, your instance will be located in our North American data center and any outbound mail will originate from these IP addresses.

FCrDNS

This is known as Forward-Confirmed reverse DNS (FCrDNS). This means that the hostname’s A record must match the reverse DNS (PTR) record for the IP (and Vice Versa). This was a historic attempt to ensure that the Sender owned the domain and the DNS record. In reality, it never really worked once cloud services or multi-tenant systems became a reality with multiple SMTP serves serving many customers and having resilience and was dropped by all but 2 lists years ago.

Therefore as with many other cloud vendors, we are advising our customers and their email recipients to avoid using any blacklist that implements FCrDNS or if not possible, configure Hornbill to use their own SMART host rather than the live.hornbill.com provided SMART HOST