When the DNS settings are implemented and a subdomain is active and connected, you might have additional questions about what the DNS setting involve and how it works. We tried to break it down:


If you're using the Nameserver (NS) or CNAME methods, we handle all of this on your behalf.


subdomain.domain.com IN A 185.154.150.15

  • What it does: Points subdomain.domain.com to an IP.
  • Why it matters: Used for domain resolution. Often this subdomain serves tracking links, open pixel tracking, or bounce management in ESPs like Maileon.

subdomain.domain.com IN MX mta.pf.xqueue.de

  • What it does: Tells the world that mta.pf.xqueue.de is the mail server for subdomain.domain.com.
  • Why it matters: Ensures replies, bounces, and other SMTP-level operations can route correctly through XQueue's infrastructure.

subdomain.domain.com IN TXT "v=spf1 include:_spf.xqueue.com ~all"

  • What it does: Says “emails from subdomain.domain.com are valid if they come from servers listed in _spf.xqueue.com.”
  • Why it matters: Helps prevent email spoofing. Receiving mail servers use this to verify that Maileon (XQueue) is authorized to send on your domain’s behalf.
  •  ~all means: "soft fail" others — not as strict as -all but still flags unauthorized servers.

xq._domainkey.subdomain.domain.com IN TXT "v=DKIM1; k=rsa; t=y:s; p=MIG[..]AQAB"

  • What it does: Publishes a public key used by recipients to verify DKIM-signed emails from Maileon.
  • Why it matters: Ensures message integrity and authenticity — that the content wasn’t changed and it’s from your domain.
  • xq is the selector Maileon uses.
  • t=y:s indicates it's in testing mode (y) and possibly limited to signing only (s) - does not affect deliverability

_dmarc.subdomain.domain.com IN TXT "v=DMARC1; p=quarantine; rua=mailto:dmarc@xqueue.com; pct=100;"

  • What it does: Tells mail receivers how to handle failing SPF/DKIM checks.
  • Why it matters: Adds another layer of protection.
  • p=quarantine: Suggests suspicious mail should go to spam.
  • rua=...: Tells receivers to send reports to XQueue for visibility.
  • pct=100: Applies the policy to 100% of messages.