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https://nih.gov

Infrastructure

· 9 checks — DNS, redirects, IPv6, crawlability, URL variants, and domain intelligence rolled into one auditable list.
SCORE
76
GRADE
C
FIX
2
REVIEW
3
PASS
4
INFO
0
Probed from Sao Paulo, Brazil
301 Moved Permanently
Checks
9
4 PASS 3 REVIEW 2 FIX
D
URL Variants
Action
www/non-www, trailing slash, HTTP→HTTPS
FIX
www/non-www, trailing slash, HTTP→HTTPS
Critical::
Both www and non-www versions serve content
Got: Both variants return 200 Expected: One variant 301-redirects to the other
Critical::
HTTP version does not redirect to HTTPS
Got: HTTP 0 Expected: 301 redirect to HTTPS

www / non-www

200https://www.nih.gov/
200https://nih.gov/

Inconsistent — duplicate content risk

HTTP → HTTPS

http://nih.gov/

HTTP version does not redirect to HTTPS

D
CDN & Delivery
Action
No CDN detected
FIX
No CDN detected
Warning::
No CDN detected
A CDN can significantly improve load times for users around the world by caching content at edge nodes closer to them.
No CDN detected

Consider using a CDN to improve global delivery speed and reduce origin load.

B
Redirect Chain
1 redirect(s), 1211 ms total
REVIEW
1 redirect(s), 1211 ms total
Info::
Single redirect
Got: https://nih.gov → https://www.nih.gov/ (301)
Info::
WWW normalization redirect
Warning::
Redirect overhead: 1211 ms total
Got: 1211 ms

https://nih.gov

598 ms · HTTP/1.0

301

https://www.nih.gov/

613 ms · HTTP/1.1 FINAL

#URLStatusTimeProtocolServer
1https://nih.gov301598 msHTTP/1.0BigIP
2https://www.nih.gov/200613 msHTTP/1.1nginx

See the visual redirect chain in the HTTP Probe tab →

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
TLS Certificate Expiry & Recommendations
304 days until leaf cert expires — 4 issues to address
REVIEW

Certificate validity

304
days left
0d 30d 60d 90d+

Recommended actions

  • Prefer TLS 1.3 — TLS 1.2 is acceptable but TLS 1.3 removes RSA key exchange and improves latency
  • Add includeSubDomains to the HSTS directive
  • Add the preload directive and submit to hstspreload.org once max-age + includeSubDomains are in place
  • Enable OCSP stapling on your TLS server to remove a CA roundtrip and protect user privacy
A
DNS Records
1 A records, 732 ms lookup
PASS
1 A records, 732 ms lookup
Info::
Resolves to 1 IPv4 address(es)
Got: 156.40.212.210
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: ns.nih.gov, ns2.nih.gov, ns3.nih.gov
Info::
8 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
Warning::
DNS resolution is slow (732 ms)
Slow DNS adds latency to every page load. Consider a faster DNS provider.
Got: 732 ms
A156.40.212.210
AAAA—
CNAME—
NSns.nih.gov, ns2.nih.gov, ns3.nih.gov
MX
10 nihcesxwayst06.hub.nih.gov
10 nihcesxwayst05.hub.nih.gov
10 nihcesxwayst04.hub.nih.gov
10 nihcesxwayst03.hub.nih.gov
10 nihcesxway3.hub.nih.gov
10 nihcesxway5.hub.nih.gov
10 nihcesxway6.hub.nih.gov
10 nihcesxway4.hub.nih.gov
TXT
da1dfl8ipaafpqsh40iiuubf7n
f71j9q2oprakr7gtedlcau485k
pbj2k0thl8k6bc1b5igtqqghls
rh426i3oiis217bktj8o4nd2m2
sv6eiguevqe64cojov3psnedd2
uub8i3goc70aj1kvl0neuhle5v
dv-ToPuPeiy2ojjpiSg4wlEEaJe
0d03wt1mlg5wy8z9pv9pv0rj21pc6137
pknf061r79fsrzbmcpgnhygf1j8nvxy8
v7959lz5pgb250x8gzt0fkg7j4x1s6bw
x1htw52vr2t3416zs29gg8lq0zkw744c
apple-domain-verification=2IrLd0KYEerfwrx6
apple-domain-verification=8VumNb91MILOLiQZ
apple-domain-verification=FTZHYv0nuXKqjeP8
apple-domain-verification=G25suhrGTYqwbLNS
apple-domain-verification=c8bb3gA2SNfmH0Zx
apple-domain-verification=rFyOPvcO8sUX2iHP
1qM+TU0yI2yC5SbKT6I96/NjwTb/86hET84vn0/fXWW=
wOUurBjukuuVfNP30Zyjv13ohvbjr9KVCgIoMfKSL6U=
docusign=5a06ea48-7158-4d7c-a47f-624b9d0cebc9
docusign=850d3223-bb46-4946-986b-2410b69ed0e7
jamf-site-verification=g8V3otVBbtqnjBIjIJXrFg
amazonses:6dUQp3PJw2/pPriaGheRkNX6rVRchTDJCVkzGLDtftA=
amazonses:93j7xtRaIBE5K+ERCErN+WDNFhQPQ1rY8mCD3Ut5Rqg=
amazonses:Ckm+FeqyUMSBHOvsBsDHWeb1nuGAr6AWg5crTuJh47k=
amazonses:EpIukSNkqrJBid632tohg9ghfR9ZOm2BsQKY8fKESvs=
amazonses:F99Cv1zG5C8JOyxlwPmjFx3qCOyQ7xJdwsNMHiJbEew=
amazonses:Oq2yjJ17I+Cqlgpxl9Pto0uQ7gwb0IpbhQFCHjPwuGo=
amazonses:QJZljHq4QVLochyWJlHRtF/TQ7CgNwoHHWnOK7AjCWo=
amazonses:QLi7vDgXZTFrD/2qNMkfcQtCzsetuefpN50b98lKPA0=
amazonses:Socb9IMK/O81TXqIP15y3NAyd8tyEcV6waygbWSPBi0=
amazonses:njYRGZSzGLGsQ66bZMwxwZZF4zHx9G8JWosbZeNa7Eo=
amazonses:rhL1YpdU4RL+Q7IALiZNww69f5cR1IZDcqEh9fRy6Tg=
amazonses:sFnUJ7LhEsJBsbZON/tFEgtZeGaqZiwY6vCL/+AJXak=
amazonses:vDxikFPIS0Am8dY/BlMuOFbJ2TuF64fRwUfkUGH67bY=
openai-domain-verification=dv-ToPuPeiy2ojjpiSg4wlEEaJe
docker-verification=6c54ab12-d26d-44b7-978e-f60aa83a02f3
miro-verification=ce1878a9901e3785a9ee9302aaaf4b8f878ff042
mongodb-site-verification=P4xvHdvjB9koHJnGWdIuapplaUGKo9VP
identrust_validate=gQ545eXspYKimJ6IrOqCZrD5ckAPWT8GjcAlRitOVlEB
webexdomainverification.2494X=72426cc0-664d-4a80-a6f4-113b7f648c9d
google-site-verification=8BC5Gnatu9NBfOph_lZpZyG2eDK0iPs0V8Li0RKzin8
google-site-verification=bFFD3VwenH37-hj5wbQqLUOAkLjsrX2Tp-LnN1AvpkQ
google-site-verification=zVNJw3i2goXwxAOFiO6ubfIWhKkgRnHS82Q7F6M6Gck
SPF v=spf1 ip4:128.231.90.64/26 ip4:165.112.13.0/26 ip4:156.40.79.128/25 ip4:128.231...
SDRQ4Pu3aj2Qhnqm0Pu+NCsKPrfBbW56qXduqE9GxA/f5eo+/Ui6umgbTg9PW0hjeg21Q2yCpOALWHqZ...
adobe-sign-verification=1e4a7a1987a2efa2d94b3cdcf717ec0b5d1dcbcb8c16a5d2bc4ea7c4...
ciscocidomainverification=1b32b084b0eb3ade21d6a521cfa1db73d2a787817950f96cf35fe6...
adobe-idp-site-verification=5e85ea0ed34d3d2a09f830d0cfc77139471d15e20e771d90484e...
cisco-ci-domain-verification=25e2351f5ed93561cf171fbead7759b2407183ca513c2c4d7eb...
webexdomainverification.4C675B897222B136E053AB06FC0A3F65=cf14e0ca-cfec-4d2b-83ab...
webexdomainverification.4C675B8A8FC5B136E053AB06FC0A3F65=81f2d6dc-b5b1-4624-9e3f...
webexdomainverification.4C675B8AEB46B136E053AB06FC0A3F65=a9568d05-1a3d-4c2b-9f45...
webexdomainverification.4C675B8AF44FB136E053AB06FC0A3F65=b1985124-e9bf-4009-a584...
atlassian-domain-verification=FfyaIO5BcqxasUU4Cuwp9/4Y3ujXrMEpfhyaPydm5lM6vqDALu...
atlassian-domain-verification=VhnxT3ISJLKFyasfowo1iyVXcEqztbz/3PWOQM6LP0kG9HrAlq...
atlassian-domain-verification=wdcwOCoxzIePKKuoOG918QCLMqYKy85i2g2UFoGlTcp32Eifql...
CAALookup not available with standard resolver
Resolved in 732 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.

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

A+
Crawlability
robots.txt present, sitemap with 2594 URLs
PASS
robots.txt present, sitemap with 2594 URLs
Info::
robots.txt is present
Got: 2027 bytes
Info::
sitemap.xml is present
Info::
sitemap.xml is valid XML
Info::
sitemap.xml contains 2594 entries
Info::
robots.txt does not reference a sitemap
Add a 'Sitemap:' directive to robots.txt so search engines can discover your sitemap.

Add a 'Sitemap:' directive to robots.txt so search engines can discover your sitemap.

Why this matters

robots.txt omits Sitemap: directive — crawlers must fetch /sitemap.xml by convention; reliable but missing the explicit hint.

Source: sitemaps.org

robots.txt 200 OK
Size 2027 B Sitemaps referenced 0 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.md
Disallow: /composer/Metapackage/README.txt
Disallow: /composer/Plugin/ProjectMessage/README.md
Disallow: /composer/Plugin/Scaffold/README.md
Disallow: /composer/Plugin/VendorHardening/README.txt
Disallow: /composer/Template/README.txt
Disallow: /modules/README.txt
Disallow: /sites/README.txt
Disallow: /themes/README.txt
Disallow: /web.config
# Paths (clean URLs)
Disallow: /admin/
Disallow: /comment/reply/
Disallow: /filter/tips
Disallow: /node/add/
Disallow: /search/
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
sitemap.xml 200 OK
Type URL Set URLs 2594 entries Valid XML Yes
Sample URLs:
A+
Domain Intelligence
nih.gov — via get.gov, 28 years, 11 months old, hosted on NIH-NET - National Institutes of Health, US
PASS
nih.gov — via get.gov, 28 years, 11 months old, hosted on NIH-NET - National Institutes of Health, US
Info::
Domain registered until Aug 22, 2026 (4 months remaining)
Info::
DNSSEC is enabled
Info::
Registrar: get.gov
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: NIH-NET - National Institutes of Health, US
Got: AS3527
Domain expiry

5 days

August 22, 2026

SSL certificate

304 days

Issued by GoDaddy.com, Inc.

Domain age

28 years, 11 months

Registered October 2, 1997

DNSSEC

Enabled

Protects against DNS spoofing

Hosting

NIH-NET - National Institutes of Health, US

ASN AS3527

156.40.212.210

Registrar

get.gov

Unlocked 3 NS records
Expiry timeline
Today
+1 year
Domain expiry SSL expiry Danger zone (≤30 days)
Recommended actions
  • Renew the domain or enable auto-renewal to prevent accidental expiry
  • Enable registrar lock (clientTransferProhibited) to block unauthorized domain transfers
Registrar get.gov
Created October 2, 1997 (28 years, 11 months ago)
Expires August 22, 2026 (4 months)
Last Updated March 4, 2026
Name Servers ns.nih.gov, ns2.nih.gov, ns3.nih.gov
DNSSEC Enabled
Registrant REDACTED FOR PRIVACY
Hosting
IP Address 156.40.212.210
ASN AS3527 (NIH-NET - National Institutes of Health, US)
Provider NIH-NET - National Institutes of Health, US
Data source: rdap (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
HTTP Probe Timing
Total 609 ms — DNS, TCP, TLS, TTFB, content transfer breakdown
PASS
DNS Lookup DNS Lookup — time to resolve the domain name to an IP address.
132 ms
TCP Connect TCP Connect — time to establish a TCP connection to the server.
118 ms
TLS Handshake TLS Handshake — time to complete the HTTPS encryption handshake.
242 ms
Time to First Byte Time to First Byte — how long the server takes to respond with the first byte of data.
609 ms
Total Time Total request time from DNS lookup through full response.
609 ms

Connection waterfall

DNS Lookup 132 ms TCP Connect 118 ms TLS Handshake 242 ms Server Processing 118 ms Content Transfer 0 ms
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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