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https://tensorflow.org

Infrastructure

· 9 checks — DNS, redirects, IPv6, crawlability, URL variants, and domain intelligence rolled into one auditable list.
SCORE
92
GRADE
A
FIX
1
REVIEW
2
PASS
6
INFO
0
Probed from Madrid, Spain
301 Moved Permanently
Checks
9
6 PASS 2 REVIEW 1 FIX
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
URL Variants
www/non-www, trailing slash, HTTP→HTTPS
REVIEW
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
Info::
HTTP correctly 301-redirects to HTTPS

www / non-www

200https://www.tensorflow.org/
200https://tensorflow.org/

Inconsistent — duplicate content risk

HTTP → HTTPS

301http://tensorflow.org/ https://www.tensorflow.org/

Consistent

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

Certificate validity

61
days left
0d 30d 60d 90d+

Recommended actions

  • Enable HSTS: Strict-Transport-Security: max-age=31536000; includeSubDomains
  • 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, 23 ms lookup
PASS
1 A records, 23 ms lookup
Info::
Resolves to 1 IPv4 address(es)
Got: 216.239.32.27
Info::
Single A record — no DNS redundancy
Multiple A records provide failover if one server goes down.
Info::
Has 1 IPv6 (AAAA) record(s)
Got: 2001:4860:4802:32::1b
Info::
4 nameserver(s) configured
Got: ns-cloud-c3.googledomains.com, ns-cloud-c1.googledomains.com, ns-cloud-c2.googledomains.com, ns-cloud-c4.googledomains.com
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::
No SPF record found in TXT records
SPF helps prevent email spoofing. Add a TXT record starting with 'v=spf1'.
Info::
DNS resolution time: 23 ms
Got: 23 ms
A216.239.32.27
AAAA2001:4860:4802:32::1b
CNAME
NSns-cloud-c3.googledomains.com, ns-cloud-c1.googledomains.com, ns-cloud-c2.googledomains.com, ns-cloud-c4.googledomains.com
MX
1 aspmx.l.google.com
5 alt1.aspmx.l.google.com
5 alt2.aspmx.l.google.com
10 alt4.aspmx.l.google.com
10 alt3.aspmx.l.google.com
TXT
google-site-verification=FO-asi2Djdtu7CEiXqj2n80rSNcub6WhE1r9L9z6oy8
google-site-verification=ZUIlu5kbb0_nreS5Lt6lvD_1SRhbVsGq6TL21s9Gaas
google-site-verification=Vkyt5mqyb-P34Ml0V8lKVja03ei0oPLCZ3ZCOBduc3Y
google-site-verification=_8hwbyJ2D3u3458Fk9vBuhCCqRwPq15MdsnMqk--yqw
google-site-verification=FAtbPSvbHZAsXSctJdRh6NqtZ9hiqh_kpHCjCZGbtK8
google-site-verification=8BeJx_QNi-UYmUtA-s_LwjRTHYaD3dUuScW6yWJ1ll0
google-site-verification=XFmqvz7DWBJ7KR-e6wgiIYl8e7o8rSUqP5j1QIM1k7o
google-site-verification=QNIZ02ik6DHanav0Ubf2AEE0Cwj3QosClem0_euvXkw
google-site-verification=X8e_3ME8hmVBfXrryoejTpijLplKKSbDDBqKUFxJULA
CAALookup not available with standard resolver
Resolved in 23 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.

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)

A
Redirect Chain
1 redirect(s), 599 ms total
PASS
1 redirect(s), 599 ms total
Info::
Single redirect
Got: https://tensorflow.org → https://www.tensorflow.org/ (301)
Info::
WWW normalization redirect
Info::
Redirect overhead: 599 ms total
Got: 599 ms

https://tensorflow.org

60 ms · HTTP/1.1

301

https://www.tensorflow.org/

539 ms · HTTP/1.1 FINAL

#URLStatusTimeProtocolServer
1https://tensorflow.org30160 msHTTP/1.1sffe
2https://www.tensorflow.org/200539 msHTTP/1.1Google Frontend

See the visual redirect chain in the HTTP Probe tab →

A+
IPv6 Readiness
IPv6 reachable (16 ms)
PASS
IPv6 reachable (16 ms)
Info::
IPv6 is configured and reachable at 2001:4860:4802:32::1b
Got: 16 ms connect
IPv6 Ready
AAAA Records 2001:4860:4802:32::1b Connection Reachable (16 ms)
A+
Crawlability
robots.txt present, sitemap with 1 URLs
PASS
robots.txt present, sitemap with 1 URLs
Info::
robots.txt is present
Got: 62 bytes
Info::
sitemap.xml is present
Info::
sitemap.xml is valid XML
Info::
sitemap.xml contains 1 entries
Info::
Sitemap index with 1 child sitemaps
Info::
robots.txt references sitemap
robots.txt 200 OK
Size 62 B Sitemaps referenced 1 User-agents * Blocking No — crawling allowed
User-agent: *
Sitemap: https://www.tensorflow.org/sitemap.xml

sitemap.xml 200 OK
Type Sitemap Index URLs 1 entries Valid XML Yes
A+
Domain Intelligence
tensorflow.org — via MarkMonitor Inc., 10 years, 9 months old
PASS
tensorflow.org — via MarkMonitor Inc., 10 years, 9 months old
Info::
Domain registered until Aug 25, 2026 (4 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: MarkMonitor Inc.
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.
Domain expiry

71 days

August 25, 2026

SSL certificate

61 days

Issued by Google Trust Services

Domain age

10 years, 9 months

Registered August 25, 2015

DNSSEC

Not enabled

Protects against DNS spoofing

Hosting

Unknown

2001:4860:4802:32::1b

Registrar

MarkMonitor Inc.

Unlocked 4 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 DNSSEC to protect visitors from DNS spoofing
  • Enable registrar lock (clientTransferProhibited) to block unauthorized domain transfers
Registrar MarkMonitor Inc.
Created August 25, 2015 (10 years, 9 months ago)
Expires August 25, 2026 (4 months)
Last Updated July 29, 2025
Name Servers ns-cloud-c1.googledomains.com, ns-cloud-c2.googledomains.com, ns-cloud-c3.googledomains.com, ns-cloud-c4.googledomains.com
DNSSEC Not enabled
Hosting
IP Address 2001:4860:4802:32::1b
Data source: rdap (0.4s)

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

A+
HTTP Probe Timing
Total 83 ms — DNS, TCP, TLS, TTFB, content transfer breakdown
PASS
DNS Lookup DNS Lookup — time to resolve the domain name to an IP address.
23 ms
TCP Connect TCP Connect — time to establish a TCP connection to the server.
16 ms
TLS Handshake TLS Handshake — time to complete the HTTPS encryption handshake.
22 ms
Time to First Byte Time to First Byte — how long the server takes to respond with the first byte of data.
83 ms
Total Time Total request time from DNS lookup through full response.
83 ms

Connection waterfall

DNS Lookup 23 ms TCP Connect 16 ms TLS Handshake 22 ms Server Processing 22 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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