Mail health monitoring

The records that keep mail deliverable, plus every sending address checked against the blocklists that actually get you rejected.

Included on every plan.

PlansFreeProBusiness
What Mail health monitoring catches
What breakshostnag
Mail stops being deliveredYes

How it works

  1. 01

    Add the mail domain

    The domain the records live on, not the mail server hostname, like example.com.

  2. 02

    hostnag reads MX, SPF, DMARC and DKIM

    DKIM is read per selector, up to ten of them, every time hostnag polls the domain.

  3. 03

    Every sending address against four blocklists

    Each MX address is checked against four public lists, always with the runner's own resolver, never a customer's.

  4. 04

    A silent lookup is never a false pass

    An area that didn't answer is left out of the report entirely, not counted as clean.

What you'll be told

What you get told

  1. [Warning] Mail setup for example.com has gaps

    No SPF record. Anyone can send mail as this domain. No DMARC record. Receivers have no policy for mail that fails SPF and DKIM.

    Mail
  2. [Warning] SPF record changed for example.com

    Now: v=spf1 include:_spf.new-provider.example ~all. Was: v=spf1 include:_spf.old-provider.example ~all.

    Mail

Sample alerts, rendered by the same code that writes your email and Slack messages.

Settings

Target
a mail domain
DKIM selectors
up to 10, comma-separated
Blocklists
4 public lists, checked with the runner's own resolver
Interval
1440 min on Free, 60 on Pro, 15 on Business

Questions

Will you use my own DNS resolver for the blocklist lookups?

No, always the runner's own. A customer's resolver could be made to hide a listing.

Do you check every mail server, or just the domain?

Every address behind every MX record for the domain.

Related

Add a host. Hear about it first.

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