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SOA · retry 1h should be shorter than refresh 1h. Current values: refresh 1h, retry 1h, expire 14d, negative TTL 1h.

DNSSEC · The earliest signature expires at 2026-10-25 15:58 UTC (in 91h0m0s). Check that automatic re-signing works.

DNSSEC · NSEC3 uses 50 iterations and a 8-byte salt. RFC 9276 recommends 0 iterations and no salt: extra iterations cost resolvers CPU and add no real protection, and some validators treat high counts as insecure.

Records · These records have a TTL below 5m, causing extra queries and slower lookups: A (1m), MX (1m). Low TTLs are useful just before a planned change.

MX · Only one MX record found. For better email reliability, consider adding at least one backup MX server.

DNSSEC · DNSKEY signatures expire at 2026-10-25T15:58:06Z (in 91h0m0s). Check that re-signing works.

DKIM · 1024-bit RSA keys are the minimum and are considered weak today: selector2 (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.

TLS · MTA-STS or DANE is used without TLS-RPT, so you get no reports when senders fail to deliver because of TLS problems. Publish _smtp._tls TXT "v=TLSRPTv1; rua=mailto:...".