Understand split DNS for reseller-hosted domains on OneNet Servers

Applies to: Current reseller-hosted domains on OneNet Servers where website traffic and email routing may point to different OneNet Servers services.

Split DNS means the website and the email side of the same domain do not necessarily point to the same place. This is common when a domain uses OneNet Servers web hosting on one service and mail delivery on another. The key is to keep the records consistent, not to keep everything on one IP by force.

Before you start

• Confirm which OneNet Servers service handles the website.
• Confirm which OneNet Servers service handles the email side for the same domain.
• If your reseller service is on a separate legacy platform, use the legacy docs for that platform instead of this Plesk-focused guide.

Steps on OneNet Servers

1. Keep the authoritative DNS on the correct OneNet Servers nameservers if OneNet Servers is meant to stay in control of the live zone.
2. Point the website records, such as the root A record and www, to the active web service.
3. Point the mail routing records, especially MX and the related authentication records, to the active mail service values.
4. After the change, test the website and the email path separately instead of assuming one test covers both.

What you should see next

• The website should resolve to the intended web service.
• Mail should still route through the intended mail service with the correct MX and authentication records in place.

Common issues

• Using the web IP in the wrong place can break mail delivery.
• Leaving SPF, DKIM, or DMARC behind on old values can create delivery problems even when the MX record looks right.

Visual guide

What usually stays split

• Web A and CNAME records stay aligned with the active web hosting service.
• MX and mail-authentication records stay aligned with the active mail service.
• TXT verification records should be added exactly where the provider that asked for them expects them.

Next steps on OneNet Servers

• Understand how authoritative DNS works on OneNet Servers
• Manage DNS records from your OneNet Servers service
• Review reseller features available in Plesk on Odinson

When to contact support: Contact support if you are unsure which exact values should stay with the web service and which ones should stay with the mail service for the same domain.