Setup

Once Hyvor Relay is installed, visit http://<server-ip>/sudo to access Sudo, the administration panel of Hyvor Relay. For fresh installations, the first user who logs in with OIDC credentials becomes a sudo user.

Let's configure your instance for best email deliverability:

(1) Web Domain

Web domain is where you access the Hyvor Relay Console, Sudo, and API. Point the web domain to one of your server's IP addresses using an A record.

Type
Host
Value
A
relay.yourdomain.com
x.x.x.x (your server IP)
💡
On Hyvor Relay Cloud, the web domain is relay.hyvor.com.

(2) Instance Domain

The instance domain and its subdomains are used for the EHLO domain in SMTP and PTR records, and it is crucial for email deliverability.

You can either:

  • Use a subdomain (ex: relay-instance.yourdomain.com) of your main domain. This must be different from the web domain.
  • Or, you can use a completely different domain (ex: yourdomain-relay.com). If you allow third-party users to send emails using your Hyvor Relay installation, this is preferable to avoid any email reputation issues with your main domain.
💡
On Hyvor Relay Cloud, the instance domain is hyvor-relay.com.

To set up the instance domain, visit Sudo (http://<web-domain>/sudo) and edit the instance domain.

Instance Domain in Hyvor Relay Sudo

Email deliverability requires several DNS records that needs to be synced with the instance. Manully changing these records can be tedious. To solve this problem, Hyvor Relay provides an in-built DNS server that can manage all the DNS records of the instance domain. To use that, set up an NS record as follows:

Type
Host
Value
NS
relay-instance.yourdomain.com
relay-ns.yourdomain.com
A
relay-ns.yourdomain.com
x.x.x.x (your server IP)

This tells the world that the DNS records of relay-instance.yourdomain.com and its subdomains are managed by Hyvor Relay DNS servers.

Redundancy
If you run multiple Hyvor Relay servers, it is recommended to set up multiple NS records pointing to different servers for redundancy. (Ex: relay-ns1.yourdomain.com pointing to one server IP and relay-ns2.yourdomain.com pointing to another server IP.)

Can't use NS records?
If you cannot use NS records due to domain registrar limitations, organizational policies, or other reasons, you can manually set up the required DNS records.

(3) PTR Records

PTR, also known as reverse DNS, is a DNS record that maps an IP address to a domain name. SMTP messages contains a EHLO <domain> command, which identifies the sending server (or IP address). In Hyvor Relay, each sending IP address uses a unique subdomain of the instance domain as the domain name.

You can find the domain name of each IP address in Sudo → Servers section.

PTR & DNS Records in Hyvor Relay Sudo

Most email providers require the sending IP address to have a PTR record that points to the domain name ("reverse DNS match") and the domain name to have an A record that points to the IP address ("forward DNS match").

Adding PTR Records

Setting PTR records is something Hyvor Relay's DNS server cannot do for you, as it requires access to the IP address's reverse DNS zone, which is usually managed by your hosting provider. Consult your hosting provider's documentation or support and set up PTR records for ALL IP addresses as shown in Sudo.

Ex:

  • 8.8.8.8 → smtp1.relay-instance.yourdomain.com
  • 9.9.9.9 → smtp2.relay-instance.yourdomain.com
There is a health check to verify PTR records. Visit Sudo → Health section to see the results.

Managing Sudo Users

You can add and remove sudo users from the command line.

  • SSH into one of the servers.
  • cd into the Hyvor Relay deployment directory.
  • docker compose exec -it app sh to enter the app container.
  • Then, use the following commands:
    • sudo:list: List all sudo users.
    • sudo:add <email>: Add a new sudo user by email.
    • sudo:remove <id>: Remove a sudo user by ID.

What's Next?

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