DNS Records
Configure the required DNS records for Microsoft 365 services on your custom domains. Proper DNS configuration ensures email delivery, auto-discovery, email authentication, and Teams federation work correctly.
Required DNS Records
MX Record (Email)
Routes email to Exchange Online:
Host: @
Points to: contoso-com.mail.protection.outlook.com
Priority: 0Autodiscover CNAME
Enables automatic Outlook configuration:
Host: autodiscover
Points to: autodiscover.outlook.comSPF Record
Prevents email spoofing:
Type: TXT
Host: @
Value: v=spf1 include:spf.protection.outlook.com -allDKIM Records
Cryptographic email signing:
Host: selector1._domainkey
Points to: selector1-contoso-com._domainkey.contoso.onmicrosoft.com
Host: selector2._domainkey
Points to: selector2-contoso-com._domainkey.contoso.onmicrosoft.comDMARC Record
Policy for handling failed authentication:
Type: TXT
Host: _dmarc
Value: v=DMARC1; p=quarantine; rua=mailto:dmarc@contoso.comTeams/SfB Records
For Teams federation and SIP:
SRV: _sipfederationtls._tcp -> sipfed.online.lync.com (Port 5061)
SRV: _sip._tls -> sipdir.online.lync.com (Port 443)
CNAME: sip -> sipdir.online.lync.com
CNAME: lyncdiscover -> webdir.online.lync.comLast updated on