Good, with 2 things to fix

cisco.com scored 84/100 (grade B). The main issues are DKIM key shorter than 2048 bits and SPF has too many lookups that return nothing. Detected senders: Microsoft 365.

Checked 2026-10-04 02:06 UTC · fresh check

3 passed2 need attention0 failing3 for informationDetected senders: Microsoft 365

All checks

MXCan servers find your inbox?No issues foundPass

Nothing to report.

SPFWho may send as you?SPF has too many lookups that return nothingNeeds attention

Warning: SPF has too many lookups that return nothing
Checking mail from cisco.com, IPv6 clients would hit 5 void lookups (DNS queries that return no data). RFC 7208 lets receivers fail SPF after 2. Remove includes and mechanisms that point at names that no longer exist, or MX hosts without an address for that family.
Info: SPF ends in softfail (~all)
"~all" is common and works well with DMARC. "-all" is stricter; switch when you are sure every sender is listed.

DKIMAre your emails signed?DKIM key shorter than 2048 bitsNeeds attention

Warning: DKIM key shorter than 2048 bits
selector1 (1024-bit) uses an RSA key below 2048 bits. Short keys can be factored and some receivers treat them as weak. Rotate to a 2048-bit key at your sending provider.
Pass: DKIM key published
cisco.com publishes a DKIM key under selector1, k2, k3, s1, s2.

DMARCWhat happens to fakes?No issues foundPass

Nothing to report.

AlignmentDoes it match your From?SPF alignment is unknownInfo

Info: SPF alignment is unknown
The SPF record of cisco.com can pass for some senders (those matched before the failing part), but another evaluation path ends in a permanent error (spf.void-lookups). Senders that reach that path fail SPF, so whether your mail aligns through SPF is unknown. Fix the error so every path evaluates.

BIMICan inboxes show your logo?No issues foundPass

Nothing to report.

MTA-STSIs mail to you encrypted?No MTA-STS recordInfo

Info: No MTA-STS record
No MTA-STS record at _mta-sts.cisco.com. MTA-STS (RFC 8461) makes sending servers require TLS and a valid certificate when delivering to you, which blocks downgrade attacks.
How to fix this

TLS-RPTWill you hear about failures?No TLS-RPT recordInfo

Info: No TLS-RPT record
No TLS reporting record at _smtp._tls.cisco.com. TLS-RPT (RFC 8460) tells senders where to send daily reports about failed encrypted deliveries to you.
How to fix this

How to fix it

Publish the MTA-STS recordTXT

Tells sending servers that cisco.com publishes an MTA-STS policy at https://mta-sts.cisco.com/.well-known/mta-sts.txt. Change the id whenever the policy file changes.

TypeTXT

Name / Host

_mta-sts.cisco.com

Some DNS providers want just “_mta-sts” here.

Value

v=STSv1; id=202610040206

Host the MTA-STS policy filepolicy-file

Serve this file over HTTPS with a valid certificate for mta-sts.cisco.com. It lists your MX hosts and starts in testing mode; switch to mode: enforce once TLS-RPT reports show no failures.

Location

https://mta-sts.cisco.com/.well-known/mta-sts.txt

Contents

version: STSv1
mode: testing
mx: alln-mx-01.cisco.com
mx: rcdn-mx-01.cisco.com
mx: aer-mx-01.cisco.com
max_age: 604800

Set up a TLS report addressinstruction

Sending servers will report TLS failures when delivering to cisco.com, which you need before enforcing MTA-STS. The address must accept TLS reports; a DMARC report address does not necessarily do so.

Applies to: _smtp._tls.cisco.com

Pick an address that will receive TLS reports: a mailbox you read (for example tls-reports@cisco.com, created first) or a TLS reporting service. 2. Publish a TXT record at _smtp._tls.cisco.com with the value v=TLSRPTv1; rua=mailto:<that address>.