On this page
Using your own domain
Aliases on alias.mom depend on us existing. Aliases on yourdomain.com do
not: if we disappear, or you get bored of us, you repoint the MX record and
every address you have handed out keeps working.
If you plan to use this seriously, do this. It is the single most important thing on this site.
The records
Add the domain in the dashboard and it shows you the exact values. There are three you need and four you want.
Required
| Type | Host | Value |
|---|---|---|
| TXT | your domain | the ownership token shown in the dashboard |
| MX | your domain | mx.alias.mom, priority 10 |
| TXT | dkim._domainkey.yourdomain.com |
v=DKIM1; k=rsa; p=... (generated per domain) |
Ownership proves it is yours. MX sends the mail here. DKIM signs your outgoing mail with a key generated for your domain and nobody else's.
Recommended
| Type | Host | Value |
|---|---|---|
| TXT | your domain | v=spf1 include:alias.mom ~all |
| TXT | _dmarc.yourdomain.com |
v=DMARC1; p=quarantine; adkim=r; aspf=r |
| TXT | _mta-sts.yourdomain.com |
v=STSv1; id=... |
| CNAME | mta-sts.yourdomain.com |
mta-sts.alias.mom |
| TXT | _smtp._tls.yourdomain.com |
v=TLSRPTv1; rua=mailto:tlsrpt@alias.mom |
SPF and DMARC are what stop your mail landing in spam, so "recommended" is doing some work there. Add them.
The MTA-STS pair is the interesting one. Publishing MTA-STS normally means
running a web server on mta-sts.yourdomain.com with a valid certificate,
forever, which is why almost nobody does it. That CNAME hands the job to us
instead. You get the protection without running anything.
Verification
We check the records and show you which are in place. DNS takes minutes to hours to propagate depending on your provider and your old TTLs; if something is missing, it is usually just not visible yet.
We keep watching
Verification is not once. We re-check periodically, and if a record disappears we tell you rather than letting mail quietly stop. DNS breaks silently and nobody notices until someone asks why they never got a reply.
Then
Turn on catch-all, which is where owning a domain stops being administrative and starts being useful.
Something here wrong or missing? Tell us. These pages live in the same repository as the code, so a correction is a one-line change.