How to Point a Subdomain to Another Server

Subdomains do not have to live where your main site lives. blog.yourdomain.com can be on a hosted platform, app.yourdomain.com on a VPS, and yourdomain.com here — all at once. It is a DNS change, nothing more.

Which record to use

A record when the destination gives you an IP address:

Type: A    Name: app    Value: 203.0.113.90

CNAME when the destination gives you a hostname:

Type: CNAME    Name: blog    Value: myblog.platform.com

Prefer a CNAME when the provider offers one. If their infrastructure moves, they update their record and yours follows — with an A record you would have to notice and edit it yourself.

Use app, not app.yourdomain.com, in the Name field. cPanel appends the domain automatically, and typing the full name produces app.yourdomain.com.yourdomain.com.

Adding it in cPanel

Domains → Zone Editor → Manage, then Add Record.

Pick the type, enter the subdomain in Name, the IP or hostname in Value, and leave TTL at 3600 — or set 300 if you expect to change it again soon.

Do not create the subdomain under Domains → Subdomains if it is hosted elsewhere. That creates a folder here and a DNS record pointing at *this* server, which is the opposite of what you want. You only need the DNS record.

If your DNS is at Cloudflare

Add the record in Cloudflare, not cPanel — cPanel's Zone Editor has no effect once nameservers point at Cloudflare.

Set the cloud to grey (DNS only) unless you specifically want Cloudflare proxying that subdomain. If the destination provider issues its own SSL certificate, an orange cloud will interfere with their validation.

SSL when the subdomain is elsewhere

This is where people get stuck.

AutoSSL on our server cannot issue a certificate for a subdomain that does not resolve to our server. It validates by requesting a file over HTTP, and that request goes to the other server, which does not have the file.

That is expected, not a fault. The provider hosting the subdomain issues its certificate, not us. Most platforms do this automatically once the DNS record points at them; some need you to confirm the domain in their panel.

If AutoSSL is failing on that subdomain, exclude it rather than fighting it: Security → SSL/TLS Status, untick the subdomain, and let the other provider handle it.

Common setups

Blog on a hosted platform — CNAME blog to their hostname, add the custom domain in their dashboard, let them issue SSL.

App on a VPS — A record app to the VPS IP, install a certificate there with Let's Encrypt.

Staging on the same account — this one *does* use Domains → Subdomains in cPanel, because it is hosted here. Add staging and AutoSSL will cover it.

Mail elsewhere — that is MX records on the root domain, not a subdomain. See our DNS records guide.

Checking it worked

nslookup app.yourdomain.com

It should return the destination's IP. Allow up to a couple of hours for propagation, and test in a private window — your browser caches DNS aggressively.

Common problems

• Subdomain still shows your main site — an old A record for it still exists. Delete it; two conflicting records is worse than one wrong one.
• "This site can't be reached" — DNS has not propagated, or the destination is not configured to answer for that hostname. Both sides need setting up.
• Certificate warning — the destination has not issued its certificate yet. Confirm the custom domain in their panel.
• CNAME rejected by cPanel — you cannot add a CNAME for a name that already has other records. Delete the conflicting record first.