mailjet.de

Delegation · None of the nameservers has an IPv6 address, so IPv6-only resolvers can't reach them.

SOA · negative caching TTL (minimum) 3m is outside 5m–1d (RFC 2308 recommends 1–3 hours). Current values: refresh 4h, retry 15m, expire 7d, negative TTL 3m.

MX · Found 7 MX records, which is more than the recommended maximum of 5. Too many MX records may indicate a misconfiguration.

DKIM · 1024-bit RSA keys are the minimum and are considered weak today: google (1024 bits). Rotate to a 2048-bit key.

DKIM · These keys have t=y, so receivers treat DKIM failures as a test: google. Remove t=y once DKIM works.

DMARC · These report addresses are in another domain that has not agreed to receive your reports, so receivers will not send them: mailto:parked@dmarc.mailjet.tech (needs mailjet.de._report._dmarc.dmarc.mailjet.tech). Ask the report provider to publish the record, or check the address.

TLS · MTA-STS is not configured, so other mail servers fall back to unencrypted delivery when TLS fails or is stripped by an attacker. Publish a _mta-sts TXT record and a policy at https://mta-sts.<domain>/.well-known/mta-sts.txt.