nort-sur-erdre.fr

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

SOA · negative caching TTL (minimum) 1m is outside 5m–1d (RFC 2308 recommends 1–3 hours). Current values: refresh 1d, retry 1h, expire 1000h, negative TTL 1m.

DMARC · DMARC policy is set to 'quarantine'. Consider upgrading to 'reject' for stronger protection once you've verified legitimate emails are passing authentication.

MX · The following MX hosts could not be resolved to IPv6 addresses: de-smtp-inbound-1.mimecast.com, de-smtp-inbound-2.mimecast.com

DMARC · DMARC policy only applies to 25% of failing mail (pct=25). Raise pct to 100 once you are confident in your setup.

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

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.