internode.on.net email servers, SPF and DMARC

internode.on.net publishes 2 MX hosts; senders try the lowest priority number first (mx-10.au-east.atmailcloud.com, 10) and fall back to the others in order.

11 other domains we checked on the same day also route mail to hosts under atmailcloud.com, with different records from internode.on.net: aapt.net.au, adam.com.au, dodo.com.au, iinet.net.au, iprimus.com.au, netspace.net.au, ozemail.com.au, singnet.com.sg and 3 more.

The record on 5 November 2026 was v=spf1 include:_spf.internode.on.net include:internode.com.au include:aspmx.pardot.com ~all.

In plain terms, it delegates to _spf.internode.on.net, internode.com.au and aspmx.pardot.com. The top level uses 3 DNS-querying terms; SPF allows 10 in total including nested includes (RFC 7208 §4.6.4).

It ends in a soft fail (~all): mail from unlisted servers should be accepted but treated as suspicious.

The record is v=DMARC1; p=reject; aspf=r; adkim=r; sp=reject;.

p=reject asks receivers to refuse mail that fails DMARC.

What that means for you: if a contact gives an @internode.on.net address and you send to them, nothing changes. But never put an @internode.on.net address in the From line of mail sent through your own tool or ESP. It can't pass DMARC for internode.on.net, and this policy tells receivers to refuse it.

internode.on.net shares mx-10.au-east.atmailcloud.com and mx-20.au-east.atmailcloud.com with optusnet.com.au. When we tested those servers for optusnet.com.au on 13 October 2026, the result was: Verifiable. The server rejects unknown recipients during the SMTP conversation.

Our checker treats @internode.on.net like any domain: syntax, MX, disposable and role checks first, then a made-up address to rule out a catch-all, then your address at RCPT TO, disconnecting without sending. We have not tested @internode.on.net itself, but its mail goes to the same servers as optusnet.com.au, so expect @internode.on.net results to follow the pattern described there. Each result carries its own reason.

DNS tells you where mail goes, not whether one person's mailbox still exists. For a list, run the whole file through a verifier before you send: invalid rows come out, risky rows (catch-all, unknown, refused) go in their own segment, and valid rows are safe to mail.