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Infrastructure

· 9 checks — DNS, redirects, IPv6, crawlability, URL variants, and domain intelligence rolled into one auditable list.
SCORE
92
GRADE
A
FIX
1
REVIEW
3
PASS
5
INFO
0
Probed from Amsterdam, Netherlands
200 OK
Checks
9
5 PASS 3 REVIEW 1 FIX
D
HTTP Probe Timing
Action
Total 2146 ms — DNS, TCP, TLS, TTFB, content transfer breakdown
FIX
DNS Lookup DNS Lookup — time to resolve the domain name to an IP address.
2.01 s
TCP Connect TCP Connect — time to establish a TCP connection to the server.
1 ms
TLS Handshake TLS Handshake — time to complete the HTTPS encryption handshake.
6 ms
Time to First Byte Time to First Byte — how long the server takes to respond with the first byte of data.
2.13 s
Total Time Total request time from DNS lookup through full response.
2.15 s

Connection waterfall

DNS Lookup 2.01 s TCP Connect 1 ms TLS Handshake 6 ms Server Processing 109 ms Content Transfer 19 ms
C
DNS Records
Action
1 A records, 2020 ms lookup
REVIEW
1 A records, 2020 ms lookup
Info::
Resolves to 1 IPv4 address(es)
Got: 150.171.109.100
Info::
Single A record — no DNS redundancy
Multiple A records provide failover if one server goes down.
Info::
Has 2 IPv6 (AAAA) record(s)
Got: 2620:1ec:29:1::45, 2620:1ec:48:1::45
Warning::
CNAME record at zone apex
A CNAME at the zone apex can break MX and NS records. Use ALIAS/ANAME or A records instead.
Got: fde-web-afd-prd-webfproj-001-eze5erb2dxckepgb.a02.azurefd.net
Info::
No NS records found
Info::
No MX records — email not configured via DNS
Info::
CAA records not checked
CAA record lookup requires a specialized DNS resolver. This check will be available in a future update.
Info::
No SPF record found in TXT records
SPF helps prevent email spoofing. Add a TXT record starting with 'v=spf1'.
Warning::
DNS resolution is slow (2020 ms)
Slow DNS adds latency to every page load. Consider a faster DNS provider.
Got: 2020 ms
A150.171.109.100
AAAA2620:1ec:29:1::45, 2620:1ec:48:1::45
CNAMEfde-web-afd-prd-webfproj-001-eze5erb2dxckepgb.a02.azurefd.net
NS
MX
TXT
CAALookup not available with standard resolver
Resolved in 2020 ms

Multiple A records provide failover if one server goes down.

Why this matters

Single A record means a single point of failure — if that IP goes down, your site is unreachable until DNS TTL expires.

Learn more

Add multiple A records for round-robin failover, or use a managed DNS provider with health-checked failover (Route 53, Cloudflare, NS1). Short TTL (60-300s) lets clients recover faster on outages.

Source: SRE practice / DNS architecture

A CNAME at the zone apex can break MX and NS records. Use ALIAS/ANAME or A records instead.

Why this matters

CNAME at the apex (example.com) breaks every other apex record (MX, TXT, NS) — DNS-protocol violation per RFC 1034.

Learn more

RFC 1034 forbids CNAME alongside other records at the same name. Some DNS providers offer ALIAS / ANAME / flattened-CNAME records that work around this — use those instead. Otherwise apex-level CNAME breaks email (no MX), domain ownership verification (no TXT), and more.

Source: RFC 1034

CAA record lookup requires a specialized DNS resolver. This check will be available in a future update.

Why this matters

Informational: CAA (Certification Authority Authorization) records weren't checked in this scan.

SPF helps prevent email spoofing. Add a TXT record starting with 'v=spf1'.

Why this matters

Without SPF, receiving servers can't validate sending IPs — your domain is easier to spoof in phishing.

Learn more

SPF complements DMARC. Both should be published. SPF records list authorized sending IPs (e.g., `v=spf1 include:_spf.google.com ~all` for Google Workspace). After publishing, verify in Google Postmaster Tools or mxtoolbox.

Source: RFC 7208 (SPF)

Slow DNS adds latency to every page load. Consider a faster DNS provider.

Why this matters

DNS resolution is slow — anycast DNS providers (Cloudflare, Route 53) typically resolve <50ms globally.

Source: DNS performance benchmarks

B
TLS Certificate Expiry & Recommendations
89 days until leaf cert expires — 3 issues to address
REVIEW

Certificate validity

89
days left
0d 30d 60d 90d+

Recommended actions

  • Submit your domain to hstspreload.org to be added to the Chrome preload list
  • 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
B
CDN & Delivery
Azure CDN (CONFIG_NOCACHE)
REVIEW
Azure CDN (CONFIG_NOCACHE)
Info::
Site is served via Azure CDN CDN
Got: x-azure-ref: 20260421T222705Z-r19b488c8b4vb7ghhC1AMSg0r80000000fhg000000005q94
Info::
CDN cache status: CONFIG_NOCACHE
CDN Detected: Azure CDN
Provider Azure CDN Cache Status CONFIG_NOCACHE Evidence x-azure-ref: 20260421T222705Z-r19b488c8b4vb7ghhC1AMSg0r80000000fhg000000005q94
A+
Redirect Chain
No redirects — direct access
PASS
No redirects — direct access
Info::
No redirects — direct access
Got: https://www.bl.uk

https://www.bl.uk

209 ms · HTTP/1.1 FINAL

#URLStatusTimeProtocolServer
1https://www.bl.uk200209 msHTTP/1.1
A+
IPv6 Readiness
IPv6 reachable (10 ms)
PASS
IPv6 reachable (10 ms)
Info::
IPv6 is configured and reachable at 2620:1ec:29:1::45, 2620:1ec:48:1::45
Got: 10 ms connect
IPv6 Ready
AAAA Records 2620:1ec:29:1::45, 2620:1ec:48:1::45 Connection Reachable (10 ms)
A+
Crawlability
robots.txt present, sitemap with 506 URLs
PASS
robots.txt present, sitemap with 506 URLs
Info::
robots.txt is present
Got: 63 bytes
Info::
sitemap.xml is present
Info::
sitemap.xml is valid XML
Info::
sitemap.xml contains 506 entries
Info::
robots.txt references sitemap
robots.txt 200 OK
Size 63 B Sitemaps referenced 1 User-agents * Blocking No — crawling allowed
User-Agent: *
Allow: /

Sitemap: https://www.bl.uk/sitemap.xml

A
URL Variants
www/non-www, trailing slash, HTTP→HTTPS
PASS
www/non-www, trailing slash, HTTP→HTTPS
Warning::
HTTP→HTTPS redirect uses 302 instead of 301
Got: 302 temporary redirect Expected: 301 permanent redirect

www / non-www

200https://www.bl.uk/
308https://bl.uk/

HTTP → HTTPS

307http://www.bl.uk/ https://www.bl.uk/

Use 301 (permanent) instead of 302 (temporary)

A+
Domain Intelligence
bl.uk — via Nominet UK, 30 years, 10 months old, hosted on Microsoft Azure
PASS
bl.uk — via Nominet UK, 30 years, 10 months old, hosted on Microsoft Azure
Info::
Domain registered until Nov 7, 2027 (1 years, 6 months remaining)
Info::
DNSSEC is not enabled
DNSSEC protects against DNS spoofing attacks. While not required, enabling DNSSEC adds an additional layer of security. Contact your DNS provider to enable it.
Info::
Registrar: Nominet UK
Warning::
Registrar lock is NOT enabled
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.
Info::
Hosting: Microsoft Azure
Got: AS8075
Domain expiry

510 days

November 7, 2027

SSL certificate

89 days

Issued by DigiCert Inc

Domain age

30 years, 10 months

Registered November 7, 1995

DNSSEC

Not enabled

Protects against DNS spoofing

Hosting

Microsoft Azure

ASN AS8075

13.107.253.67

Registrar

Nominet UK

Unlocked 4 NS records
Expiry timeline
Today
+1 year
Domain expiry SSL expiry Danger zone (≤30 days)
Recommended actions
  • Enable DNSSEC to protect visitors from DNS spoofing
  • Enable registrar lock (clientTransferProhibited) to block unauthorized domain transfers
Registrar Nominet UK
Created November 7, 1995 (30 years, 10 months ago)
Expires November 7, 2027 (1 years, 6 months)
Last Updated December 1, 2025
Name Servers ns1-06.azure-dns.com., ns2-06.azure-dns.net., ns3-06.azure-dns.org., ns4-06.azure-dns.info.
DNSSEC Not enabled
Registrant The British Library
Hosting
IP Address 13.107.253.67
ASN AS8075 (MICROSOFT-CORP-MSN-AS-BLOCK - Microsoft Corporation, US)
Provider Microsoft Azure
Data source: rdap (2.2s)

DNSSEC protects against DNS spoofing attacks. While not required, enabling DNSSEC adds an additional layer of security. Contact your DNS provider to enable it.

Why this matters

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.

Why this matters

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

All checks on this page are automated. Results are estimates - run targeted manual reviews when the score affects a release decision.

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