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https://sheffield.ac.uk

Infrastructure

· 9 checks — DNS, redirects, IPv6, crawlability, URL variants, and domain intelligence rolled into one auditable list.
SCORE
92
GRADE
A
FIX
0
REVIEW
3
PASS
6
INFO
0
Probed from Madrid, Spain
200 OK
Checks
9
6 PASS 3 REVIEW
C
IPv6 Readiness
Action
No IPv6 support
REVIEW
No IPv6 support
Info::
No IPv6 (AAAA) records found
IPv6 support is increasingly important for global accessibility. About 40% of internet users have IPv6 connectivity.
No IPv6 Support
About 40% of internet users have IPv6. Consider adding AAAA records.

IPv6 support is increasingly important for global accessibility. About 40% of internet users have IPv6 connectivity.

Why this matters

No AAAA records — same impact as 'no IPv6 (AAAA) records'; IPv6-preferring clients pay extra latency falling back to IPv4.

Source: Google IPv6 stats

B
HTTP Probe Timing
Total 1190 ms — DNS, TCP, TLS, TTFB, content transfer breakdown
REVIEW
DNS Lookup DNS Lookup — time to resolve the domain name to an IP address.
1.03 s
TCP Connect TCP Connect — time to establish a TCP connection to the server.
30 ms
TLS Handshake TLS Handshake — time to complete the HTTPS encryption handshake.
62 ms
Time to First Byte Time to First Byte — how long the server takes to respond with the first byte of data.
1.17 s
Total Time Total request time from DNS lookup through full response.
1.19 s

Connection waterfall

DNS Lookup 1.03 s TCP Connect 30 ms TLS Handshake 62 ms Server Processing 43 ms Content Transfer 25 ms
B
TLS Certificate Expiry & Recommendations
41 days until leaf cert expires — 3 issues to address
REVIEW

Certificate validity

41
days left
0d 30d 60d 90d+

Recommended actions

  • 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 Records
1 A records, 99 ms lookup
PASS
1 A records, 99 ms lookup
Info::
Resolves to 1 IPv4 address(es)
Got: 143.167.2.102
Info::
Single A record — no DNS redundancy
Multiple A records provide failover if one server goes down.
Info::
No IPv6 (AAAA) records
Info::
3 nameserver(s) configured
Got: acheron.shef.ac.uk, hippo.shef.ac.uk, ns4.ja.net
Info::
5 mail exchanger(s) configured
Info::
CAA records not checked
CAA record lookup requires a specialized DNS resolver. This check will be available in a future update.
Info::
SPF record present in TXT
Info::
DNS resolution time: 99 ms
Got: 99 ms
A143.167.2.102
AAAA—
CNAME—
NSacheron.shef.ac.uk, hippo.shef.ac.uk, ns4.ja.net
MX
1 aspmx.l.google.com
5 alt2.aspmx.l.google.com
5 alt1.aspmx.l.google.com
10 alt4.aspmx.l.google.com
10 alt3.aspmx.l.google.com
TXT
SPF v=spf1 ip4:143.167.0.0/16 ip4:95.172.88.0/22 ip4:130.88.36.5 ip4:80.93.168.194 i...
google-site-verification=xecQmyR2UQAd3OiZbAW_FJHFJPwg8p8uX30nW4o6zOY
fastly-domain-delegation-nswth4upxeqnqveipseg-00624106-2026-03-04
successfactors-site-verification=NjRiOGZiYTRiNmU4MDQ1OWJmZjliM2IxNmQ0NDJmNWU5OTh...
miro-verification=680d07755b726a339f00d8138d67241398cd5b07
google-site-verification=58EFIopIAqD2iSA4Lo5PQGuys6Co_ojiogpJzH-Ht8E
piktochart-site-verification=h5VvjYd6x5Po8IJe2DhIExBmUzA8SvCv2B32
google-site-verification=UeOlua34rGuYEYg93SzgMHespVf9e1zfDiPd7O3xJJA
apple-domain-verification=8FCPtnPTCYc6gGWj
CAALookup not available with standard resolver
Resolved in 99 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

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.

A+
Redirect Chain
No redirects — direct access
PASS
No redirects — direct access
Info::
No redirects — direct access
Got: https://sheffield.ac.uk

https://sheffield.ac.uk

138 ms · HTTP/1.1 FINAL

#URLStatusTimeProtocolServer
1https://sheffield.ac.uk200138 msHTTP/1.1
A+
Crawlability
robots.txt present, sitemap with 2 URLs
PASS
robots.txt present, sitemap with 2 URLs
Info::
robots.txt is present
Got: 1783 bytes
Info::
sitemap.xml is present
Info::
sitemap.xml is valid XML
Info::
sitemap.xml contains 2 entries
Info::
Sitemap index with 2 child sitemaps
Info::
robots.txt references sitemap
robots.txt 200 OK
Size 1783 B Sitemaps referenced 1 User-agents * Blocking No — crawling allowed
#
# robots.txt
#
# This file is to prevent the crawling and indexing of certain parts
# of your site by web crawlers and spiders run by sites like Yahoo!
# and Google. By telling these "robots" where not to go on your site,
# you save bandwidth and server resources.
#
# This file will be ignored unless it is at the root of your host:
# Used:    http://example.com/robots.txt
# Ignored: http://example.com/site/robots.txt
#
# For more information about the robots.txt standard, see:
# http://www.robotstxt.org/robotstxt.html

User-agent: *
# CSS, JS, Images
Allow: /core/*.css$
Allow: /core/*.css?
Allow: /core/*.js$
Allow: /core/*.js?
Allow: /core/*.gif
Allow: /core/*.jpg
Allow: /core/*.jpeg
Allow: /core/*.png
Allow: /core/*.svg
Allow: /profiles/*.css$
Allow: /profiles/*.css?
Allow: /profiles/*.js$
Allow: /profiles/*.js?
Allow: /profiles/*.gif
Allow: /profiles/*.jpg
Allow: /profiles/*.jpeg
Allow: /profiles/*.png
Allow: /profiles/*.svg
# Directories
Disallow: /core/
Disallow: /profiles/
# Files
Disallow: /README.txt
Disallow: /web.config
# Paths (clean URLs)
Disallow: /admin/
Disallow: /comment/reply/
Disallow: /filter/tips
Disallow: /node/add/
Disallow: /search/
Disallow: /find
Disallow: /user/register
Disallow: /user/password
Disallow: /user/login
Disallow: /user/logout
Disallow: /media/oembed
Disallow: /*/media/oembed
# Paths (no clean URLs)
Disallow: /index.php/admin/
Disallow: /index.php/comment/reply/
Disallow: /index.php/filter/tips
Disallow: /index.php/node/add/
Disallow: /index.php/search/
Disallow: /index.php/user/password
Disallow: /index.php/user/register
Disallow: /index.php/user/login
Disallow: /index.php/user/logout
Disallow: /index.php/media/oembed
Disallow: /index.php/*/media/oembed

# Site Maps
Sitemap: https://www.sheffield.ac.uk/sitemap.xml
sitemap.xml 200 OK
Type Sitemap Index URLs 2 entries Valid XML Yes
Child Sitemaps:
A+
URL Variants
www/non-www, trailing slash, HTTP→HTTPS
PASS
www/non-www, trailing slash, HTTP→HTTPS
Info::
www/non-www redirect configured correctly (preferred: non-www)
Info::
HTTP correctly 301-redirects to HTTPS

www / non-www

301https://www.sheffield.ac.uk/
200https://sheffield.ac.uk/

Preferred variant: non-www

HTTP → HTTPS

301http://sheffield.ac.uk/ → https://www.sheffield.ac.uk/

Consistent

A+
Domain Intelligence
sheffield.ac.uk — via No registrar listed. This domain is directly registered with Nominet., hosted on JANET Jisc Services Limited, GB
PASS
sheffield.ac.uk — via No registrar listed. This domain is directly registered with Nominet., hosted on JANET Jisc Services Limited, GB
Info::
Registrar: No registrar listed. This domain is directly registered with Nominet.
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: JANET Jisc Services Limited, GB
Got: AS786
Domain expiry

Unknown

SSL certificate

41 days

Issued by Sectigo Limited

Domain age

Unknown

DNSSEC

Status unknown

Protects against DNS spoofing

Hosting

JANET Jisc Services Limited, GB

ASN AS786

143.167.2.102

Registrar

No registrar listed. This domain is directly registered with Nominet.

Unlocked 7 NS records
Expiry timeline
Today
+1 year
SSL expiry Danger zone (≤30 days)
Recommended actions
  • Enable registrar lock (clientTransferProhibited) to block unauthorized domain transfers
Registrar No registrar listed. This domain is directly registered with Nominet.
Name Servers ns0.ja.net, ns2.ja.net, ns3.ja.net, ns4.ja.net, auth03.ns.uu.net, ns1.surfnet.nl, dns-3.dfn.de
Registrant The JNT Association
Hosting
IP Address 143.167.2.102
ASN AS786 (JANET Jisc Services Limited, GB)
Provider JANET Jisc Services Limited, GB
Data source: whois (0.9s)

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

A+
CDN & Delivery
Fastly (MISS, HIT)
PASS
Fastly (MISS, HIT)
Info::
Site is served via Fastly CDN
Got: x-served-by: cache-lcy-egml8630075-LCY
Info::
CDN cache status: MISS, HIT
CDN Detected: Fastly
Provider Fastly Cache Status MISS, HIT Evidence x-served-by: cache-lcy-egml8630075-LCY
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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