> ## Documentation Index > Fetch the complete documentation index at: https://docs.lettr.com/llms.txt > Use this file to discover all available pages before exploring further. # Porkbun > Configure Porkbun DNS for Lettr: add CNAME, DKIM, DMARC, and MX records to set up sending, inbound, tracking, and storage domains. This guide walks you through adding the required DNS records for Lettr using Porkbun's DNS management. Porkbun is an affordable domain registrar that offers DNS hosting for domains registered through its [Porkbun dashboard](https://porkbun.com). You will configure a **sending domain** (CNAME, DKIM TXT, and DMARC TXT records) and, optionally, an **inbound domain** (MX records), **tracking domain** (two CNAME records), and **storage domain** (CNAME and two TXT records). *** ## Sending Domain Setup A sending domain authenticates your outgoing emails with DKIM and DMARC, ensuring they are delivered reliably and not marked as spam. This requires a CNAME record for domain verification, a TXT record for DKIM signing, and a TXT record for DMARC policy. To create a sending domain in Lettr: 1. Select **Domains** in the navigation panel 2. Select **Sending Domains** 3. Click **Create Sending Domain** 4. Enter your desired sending subdomain (e.g. `mailing.company.com`) 5. Click **Create Domain** Use a subdomain (e.g. `mailing.company.com`) instead of the root domain (`company.com`). A subdomain provides proper reputation segmentation and is required if you also plan to receive emails with Lettr. Click your new domain in the Sending Domains list. This will display a list of DNS records that need to be configured. Keep this page open — you will need these values soon. ### Configure Porkbun DNS Log in to your [Porkbun dashboard](https://porkbun.com) and navigate to **Domain Management**. Hover over your domain name and click the **DNS** link that appears inline to access the DNS record management page. If your domain was purchased through Porkbun or your nameservers already point to Porkbun, skip nameserver configuration entirely. Your domain is already using Porkbun's nameservers by default — proceed directly to adding the DNS records below. If you registered your domain elsewhere but want to manage DNS on Porkbun, you must first **update the nameservers** at your registrar to Porkbun's nameservers shown in your domain settings. Until the nameservers are updated, any records you add in Porkbun will not resolve. ### Add CNAME Record The CNAME record verifies domain ownership with Lettr's email infrastructure. Copy the CNAME values from Lettr to Porkbun: 1. In the DNS management page, select **CNAME** from the **Type** dropdown. 2. Copy the **Hostname** from Lettr and paste it into the **Host** field (without your domain suffix). For example, paste only `mailing`. 3. Copy the **Value** from Lettr and paste it into the **Answer** field. 4. Leave **TTL** at the default. 5. Click **Save**. Porkbun automatically appends your domain to the Host field. Always paste only the subdomain portion (e.g. `mailing`, not `mailing.company.com`). ### Add TXT Record (DKIM) The DKIM record adds a cryptographic signature to your outgoing emails, allowing recipients to verify they were sent by an authorized sender. Copy the TXT values from Lettr to Porkbun: 1. In the DNS management page, select **TXT** from the **Type** dropdown. 2. Copy the **Hostname** from Lettr and paste it into the **Host** field (without your domain suffix). For example, paste only `scph0126._domainkey.mailing`. 3. Copy the **Value** from Lettr and paste it into the **Answer** field. 4. Leave **TTL** at the default. 5. Click **Save**. Porkbun automatically appends your domain to the Host field. Always paste only the subdomain portion (e.g. `scph0126._domainkey.mailing`, not `scph0126._domainkey.mailing.company.com`). ### Add TXT Record (DMARC) The DMARC record tells receiving mail servers how to handle emails that fail authentication checks, protecting your domain from spoofing. Copy the TXT values from Lettr to Porkbun: 1. In the DNS management page, select **TXT** from the **Type** dropdown. 2. Copy the **Hostname** from Lettr and paste it into the **Host** field (without your domain suffix). For example, paste only `_dmarc.mailing`. 3. Copy the **Value** from Lettr and paste it into the **Answer** field. 4. Leave **TTL** at the default. 5. Click **Save**. Porkbun automatically appends your domain to the Host field. Always paste only the subdomain portion (e.g. `_dmarc.mailing`, not `_dmarc.mailing.company.com`). ### Verify Your Sending Domain After adding all three DNS records, go back to Lettr and click **Verify DNS Records**. DNS propagation can take up to 24–48 hours, though it typically completes within a few minutes. *** ## Inbound Domain Setup An inbound domain allows Lettr to receive emails on your behalf. This requires three MX records that direct incoming mail to Lettr's mail servers. ### Add Inbound Domain to Lettr To create an Inbound domain in Lettr: 1. Select **Domains** in the navigation panel 2. Select **Inbound Domains** 3. Click **Create Inbound Domain** 4. Enter your desired inbound subdomain (e.g. `inbound.company.com`) 5. Click **Create Domain**. Click on your new domain in the Inbound Domains list. This will display the MX records that need to be configured. ### Add MX Records MX records tell other mail servers where to deliver emails addressed to your domain. Copy the MX values from Lettr to Porkbun: 1. In the DNS management page, select **MX** from the **Type** dropdown. 2. Copy the **Hostname** from Lettr and paste it into the **Host** field (without your domain suffix). For example, paste only `inbound`. 3. Copy the first **Required MX Record** value (without the priority number) from Lettr (e.g. `rx1.sparkpostmail.com`) and paste it into the **Answer** field. 4. Set **Priority** to `10`. 5. Leave **TTL** at the default. 6. Click **Save**. 7. Repeat this process for the second (`rx2.sparkpostmail.com`) and third (`rx3.sparkpostmail.com`) MX records, each with priority `10`. Porkbun automatically appends your domain to the Host field. Always paste only the subdomain portion (e.g. `inbound`, not `inbound.company.com`). Adding MX records to a domain or subdomain will route all incoming email for that address to Lettr. Use a dedicated subdomain (e.g. `inbound.company.com`) to avoid affecting your primary email. ### Verify Your Inbound Domain After adding all three MX records, go back to Lettr and click **Verify DNS Records**. DNS propagation can take up to 24–48 hours, though it typically completes within a few minutes. *** ## Tracking Domain Setup A tracking domain allows Lettr to track email opens and link clicks using your own custom domain instead of the default Lettr tracking domain. This requires two CNAME records: one for the SSL certificate and one for routing tracking traffic to Lettr's infrastructure. ### Add Tracking Domain to Lettr To create a Tracking domain in Lettr: 1. Select **Domains** in the navigation panel 2. Select **Tracking Domains** 3. Click **Create Tracking Domain** 4. Enter your desired tracking subdomain (e.g. `tracking.company.com`) 5. Click **Create Domain** Click on your new domain in the Tracking Domains list. This will display the CNAME records that need to be configured. ### Add SSL Certificate CNAME Record The SSL Certificate CNAME record provisions an SSL certificate for your custom tracking domain, enabling secure HTTPS connections for tracked links. Add the record in Porkbun: 1. In the DNS management page, select **CNAME** from the **Type** dropdown. 2. Copy the **Hostname** from Lettr and paste it into the **Host** field (without your domain suffix). 3. Copy the **Value** from Lettr and paste it into the **Answer** field. 4. Leave **TTL** at the default. 5. Click **Save**. Porkbun automatically appends your domain to the Host field. Always paste only the subdomain portion (e.g. `tracking`, not `tracking.company.com`). ### Add Traffic CNAME Record The Traffic CNAME record routes click and open tracking requests from your custom domain to Lettr's tracking servers. Add the record in Porkbun: 1. In the DNS management page, select **CNAME** from the **Type** dropdown. 2. Copy the **Hostname** from Lettr and paste it into the **Host** field (without your domain suffix). 3. Copy the **Value** from Lettr and paste it into the **Answer** field. 4. Leave **TTL** at the default. 5. Click **Save**. Porkbun automatically appends your domain to the Host field. Always paste only the subdomain portion (e.g. `tracking`, not `tracking.company.com`). ### Verify Your Tracking Domain After adding both CNAME records, go back to Lettr and click **Verify DNS Records**. *** ## Storage Domain Setup A storage domain lets you serve email assets (images, attachments) from your own custom domain instead of the default Lettr storage URL. This requires two TXT records for certificate validation and ownership verification, and a CNAME record for routing asset requests to Lettr's storage infrastructure. ### Add Storage Domain to Lettr To create a Storage domain in Lettr: 1. Select **Domains** in the navigation panel 2. Select **Storage Domains** 3. Click **Create Storage Domain** 4. Enter your desired storage subdomain (e.g. `assets.company.com`) 5. Click **Create Domain** Click on your new domain in the Storage Domains list. This will display the TXT and CNAME records that need to be configured. ### Add TXT Record (Certificate Validation) The Certificate Validation TXT record provisions an SSL certificate for your custom storage domain, enabling secure HTTPS delivery of email assets. Add the record in Porkbun: 1. In the DNS management page, select **TXT** from the **Type** dropdown. 2. Copy the **Hostname** from Lettr and paste it into the **Host** field (without your domain suffix). 3. Copy the **Value** from Lettr and paste it into the **Answer** field. 4. Leave **TTL** at the default. 5. Click **Save**. Porkbun automatically appends your domain to the Host field. Always paste only the subdomain portion (e.g. `assets`, not `assets.company.com`). ### Add TXT Record (Hostname Pre-validation) The Hostname Pre-validation TXT record verifies ownership of the storage domain before Lettr provisions a custom hostname for it. Add the record in Porkbun: 1. In the DNS management page, select **TXT** from the **Type** dropdown. 2. Copy the **Hostname** from Lettr and paste it into the **Host** field (without your domain suffix). 3. Copy the **Value** from Lettr and paste it into the **Answer** field. 4. Leave **TTL** at the default. 5. Click **Save**. Porkbun automatically appends your domain to the Host field. Always paste only the subdomain portion (e.g. `assets`, not `assets.company.com`). ### Add CNAME Record (Domain Routing) The Domain Routing CNAME record routes asset requests from your custom domain to Lettr's storage infrastructure. Add the record in Porkbun: 1. In the DNS management page, select **CNAME** from the **Type** dropdown. 2. Copy the **Hostname** from Lettr and paste it into the **Host** field (without your domain suffix). 3. Copy the **Value** from Lettr and paste it into the **Answer** field. 4. Leave **TTL** at the default. 5. Click **Save**. Porkbun automatically appends your domain to the Host field. Always paste only the subdomain portion (e.g. `assets`, not `assets.company.com`). ### Verify Your Storage Domain After adding all three records, go back to Lettr and click **Verify DNS Records**. *** ## Troubleshooting Porkbun automatically appends your domain name to whatever you enter in the **Host** field. If you paste the full hostname (e.g. `mailing.company.com`), the resulting record will be `mailing.company.com.company.com`, which will fail verification. Always paste only the subdomain portion (e.g. `mailing`, `scph0126._domainkey.mailing`, `_dmarc.mailing`). Porkbun's DNS is powered by Cloudflare's infrastructure, so records typically propagate within minutes. If verification fails after adding records, check the following: * **Wait at least 30 minutes** before your first verification attempt. Most records propagate within 1–2 hours. * **Confirm the records exist** using command-line tools: ```bash theme={null} # Check CNAME record dig CNAME mailing.yourdomain.com +short # Check DKIM record dig TXT scph0126._domainkey.mailing.yourdomain.com +short # Check DMARC record dig TXT _dmarc.mailing.yourdomain.com +short # Check MX records (inbound) dig MX inbound.yourdomain.com +short # Check tracking domain CNAME dig CNAME track.yourdomain.com +short # Check storage domain CNAME dig CNAME assets.yourdomain.com +short ``` * **Use a web tool** like [WhatsMyDNS](https://www.whatsmydns.net) or [dnschecker.org](https://dnschecker.org) to verify propagation across multiple DNS servers worldwide. A common mistake is selecting the wrong record type from the **Type** dropdown: | Record | Correct Type | | ------------------------------- | ------------ | | Sending verification | CNAME | | DKIM | TXT | | DMARC | TXT | | Inbound mail | MX | | Tracking SSL certificate | CNAME | | Tracking traffic | CNAME | | Storage certificate validation | TXT | | Storage hostname pre-validation | TXT | | Storage domain routing | CNAME | The DKIM TXT value is a long string. After saving the record, re-open the DNS management page and confirm the full value is displayed in the **Answer** field. If it appears truncated, delete the record and re-add it, pasting the full value carefully. If Porkbun rejects the value due to length, you may need to split the DKIM key into two quoted strings within the same TXT record. For example: ``` "v=DKIM1; k=rsa; p=MIIBIjANBgkqhkiG9w0BAQEFAAOC..." "AQ8AMIIBCgKCAQEA..." ``` Each quoted segment must be 255 characters or fewer. Paste both quoted strings as a single value in the **Answer** field. If your records are saved in Porkbun but not resolving, confirm that your domain is using Porkbun's nameservers. You can check this with: ```bash theme={null} dig NS yourdomain.com +short ``` The output should include Porkbun nameservers. If it shows a different provider's nameservers, update them in your domain registrar settings. If your DNS records are correctly configured (confirmed with `dig` or dnschecker.org) and verification still fails after 48 hours, contact Lettr support at **[support@lettr.com](mailto:support@lettr.com)** or through the in-app chat. Include your domain name and the output of the `dig` commands above. *** ## Related Topics Learn about sending domain setup, SPF, DKIM, and DMARC. Configure MX records to receive emails with Lettr. Set up a custom tracking domain for click and open tracking. Serve email assets from your own custom domain. Understand domain types and how they work in Lettr. Troubleshoot common DNS configuration and propagation issues.