Infrastructure
· 9 checks — DNS, redirects, IPv6, crawlability, URL variants, and domain intelligence rolled into one auditable list.BURL Variantswww/non-www, trailing slash, HTTP→HTTPSREVIEW
www / non-www
Inconsistent — duplicate content risk
HTTP → HTTPS
Consistent
BTLS Certificate Expiry & Recommendations58 days until leaf cert expires — 4 issues to addressREVIEW
Certificate validity
Recommended actions
- Extend HSTS max-age to at least 31536000 (1 year) to meet the preload list criteria
- Add includeSubDomains to the HSTS directive
- Enable DNSSEC on your domain for DNS spoofing protection
- Enable OCSP stapling on your TLS server to remove a CA roundtrip and protect user privacy
A+DNS Records2 A records, 8 ms lookupPASS
| A | 104.18.30.156, 104.18.31.156 |
| AAAA | 2606:4700::6812:1e9c, 2606:4700::6812:1f9c |
| CNAME | — |
| NS | blue.foundationdns.org, blue.foundationdns.com, blue.foundationdns.net |
| MX | 5 eu-smtp-inbound-1.mimecast.com 10 eu-smtp-inbound-2.mimecast.com |
| TXT | 0ed1fe018a6ece01656c2f45e892b02f450de96d6a MS=ms54616200 Mosyle-verification- 1770668849 apple-domain-verification=ND7TUlTdAgIwm06n google-site-verification=2zC3lzIuNm90jAQfDYo1m5Z7xIs7u7VMKEoZhJII7oA google-site-verification=BuFr9DolrVy9w2345Pwewmu88bGrAwWaejPFkkyMa2k l1mdn7ufdbvph7l4c6v8csvt66 sophos-domain-verification=423504ddb7409b5ac5f630c8683ba0d4695acea93505c68e303e2... SPF v=spf1 mx include:eu._netblocks.mimecast.com include:spf.dynect.net include:em.n... |
| CAA | Lookup not available with standard resolver |
CAA record lookup requires a specialized DNS resolver. This check will be available in a future update.
Informational: CAA (Certification Authority Authorization) records weren't checked in this scan.
ARedirect Chain1 redirect(s), 739 ms totalPASS
https://nationalgallery.org.uk
249 ms · HTTP/1.1
https://www.nationalgallery.org.uk/
490 ms · HTTP/1.1 FINAL
| # | URL | Status | Time | Protocol | Server |
|---|---|---|---|---|---|
| 1 | https://nationalgallery.org.uk | 302 | 249 ms | HTTP/1.1 | cloudflare |
| 2 | https://www.nationalgallery.org.uk/ | 200 | 490 ms | HTTP/1.1 | cloudflare |
See the visual redirect chain in the HTTP Probe tab →
If permanent, use 301 instead.
302 (Found) is for genuinely temporary redirects — if this redirect is permanent, switch to 301 to preserve SEO equity.
Learn more ▾ ▴
Search engines treat 302 as temporary, keeping the original URL indexed and not transferring full link equity to the destination. Use 301 (Moved Permanently) for permanent redirects (HTTP→HTTPS, www-vs-non-www, URL restructures).
Source: Google Search Central
A+IPv6 ReadinessIPv6 reachable (2 ms)PASS
A+Crawlabilityrobots.txt present, sitemap with 7615 URLsPASS
# robots.txt for www.nationalgallery.org.uk
User-agent: *
Sitemap: https://www.nationalgallery.org.uk/xml-sitemap
Sitemap: https://www.nationalgallery.org.uk/research/research-centre/archive/sitemap/1
Sitemap: https://www.nationalgallery.org.uk/research/research-centre/archive/sitemap/2
Sitemap: https://www.nationalgallery.org.uk/research/research-centre/archive/sitemap/3
Disallow: /custom/popups
Disallow: /external
User-agent: Googlebot-Image
Disallow: /server.iip
A+Domain Intelligencenationalgallery.org.uk — via JISC Services Limited, 29 years, 1 months oldPASS
423 days
August 13, 2027
58 days
Issued by Google Trust Services
29 years, 1 months
Registered August 13, 1997
Not enabled
Protects against DNS spoofing
Unknown
2606:4700::6812:1e9c
JISC Services Limited
Expiry timeline
Recommended actions
- Enable DNSSEC to protect visitors from DNS spoofing
- Enable registrar lock (clientTransferProhibited) to block unauthorized domain transfers
DNSSEC protects against DNS spoofing attacks. While not required, enabling DNSSEC adds an additional layer of security. Contact your DNS provider to enable it.
Without DNSSEC, an attacker who can poison your DNS can hijack your domain — and SSL certs alone don't stop them.
Learn more ▾ ▴
DNSSEC adds cryptographic signatures to DNS records, preventing forged responses from poisoning resolver caches. Without it, an attacker who controls the network path can redirect your domain to a malicious server before any HTTPS handshake happens. Most modern registrars (Cloudflare, Google Domains, Route 53) enable it with one toggle.
Source: ICANN / RFC 4033
The domain can be transferred without an unlock step. Enable registrar lock (clientTransferProhibited) in your registrar's control panel to protect against unauthorized or accidental transfers.
Without registrar lock, an attacker who phishes your registrar credentials can transfer the domain in minutes — total brand hijack.
Learn more ▾ ▴
Registrar lock (clientTransferProhibited, clientUpdateProhibited, clientDeleteProhibited) requires extra verification before any transfer/update/delete. Every major registrar offers it free. Combined with 2FA on your registrar account, it's the strongest defense against domain hijacking.
Source: ICANN / domain-security best practice