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Infrastructure

· 9 checks — DNS, redirects, IPv6, crawlability, URL variants, and domain intelligence rolled into one auditable list.
SCORE
97
GRADE
A+
FIX
0
REVIEW
1
PASS
8
INFO
0
Probed from Madrid, Spain
200 OK
Checks
9
8 PASS 1 REVIEW
B
TLS Certificate Expiry & Recommendations
83 days until leaf cert expires — 3 issues to address
REVIEW

Certificate validity

83
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
A
DNS Records
1 A records, 40 ms lookup
PASS
1 A records, 40 ms lookup
Info::
Resolves to 1 IPv4 address(es)
Got: 23.185.0.3
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: 2620:12a:8001::3, 2620:12a:8000::3
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'.
Info::
DNS resolution time: 40 ms
Got: 40 ms
A23.185.0.3
AAAA2620:12a:8001::3, 2620:12a:8000::3
CNAME
NS
MX
TXT
CAALookup not available with standard resolver
Resolved in 40 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
No redirects — direct access
PASS
No redirects — direct access
Info::
No redirects — direct access
Got: https://www.cncf.io

https://www.cncf.io

8 ms · HTTP/1.1 FINAL

#URLStatusTimeProtocolServer
1https://www.cncf.io2008 msHTTP/1.1nginx
A+
IPv6 Readiness
IPv6 reachable (0 ms)
PASS
IPv6 reachable (0 ms)
Info::
IPv6 is configured and reachable at 2620:12a:8001::3, 2620:12a:8000::3
Got: 0 ms connect
IPv6 Ready
AAAA Records 2620:12a:8001::3, 2620:12a:8000::3 Connection Reachable (0 ms)
A+
Crawlability
robots.txt present, sitemap with 3101 URLs
PASS
robots.txt present, sitemap with 3101 URLs
Info::
robots.txt is present
Got: 115 bytes
Info::
sitemap.xml is present
Info::
sitemap.xml is valid XML
Info::
sitemap.xml contains 3101 entries
Info::
robots.txt references sitemap
robots.txt 200 OK
Size 115 B Sitemaps referenced 1 User-agents * Blocking No — crawling allowed
User-agent: *
Disallow: /wp/wp-admin/
Allow: /wp/wp-admin/admin-ajax.php

Sitemap: https://www.cncf.io/sitemap.xml

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: www)
Info::
HTTP correctly 301-redirects to HTTPS

www / non-www

200https://www.cncf.io/
301https://cncf.io/

Preferred variant: www

HTTP → HTTPS

301http://www.cncf.io/ https://www.cncf.io/

Consistent

A+
Domain Intelligence
cncf.io — via 1API GmbH, 10 years, 10 months old
PASS
cncf.io — via 1API GmbH, 10 years, 10 months old
Info::
Domain registered until Jul 16, 2026 (3 months remaining)
Info::
Registrar: 1API GmbH
Domain expiry

31 days

July 16, 2026

SSL certificate

83 days

Issued by Let's Encrypt

Domain age

10 years, 10 months

Registered July 16, 2015

DNSSEC

Status unknown

Protects against DNS spoofing

Hosting

Unknown

2620:12a:8001::3

Registrar

1API GmbH

Lock status unknown 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
Registrar 1API GmbH
Created July 16, 2015 (10 years, 10 months ago)
Expires July 16, 2026 (3 months)
Last Updated November 26, 2025
Name Servers ns1.dnsimple.com, ns3.dnsimple.com, ns4.dnsimple-edge.org, ns2.dnsimple-edge.net
Registrant The Linux Foundation
Hosting
IP Address 2620:12a:8001::3
Data source: whois (0.9s)
A+
HTTP Probe Timing
Total 148 ms — DNS, TCP, TLS, TTFB, content transfer breakdown
PASS
DNS Lookup DNS Lookup — time to resolve the domain name to an IP address.
27 ms
TCP Connect TCP Connect — time to establish a TCP connection to the server.
0 ms
TLS Handshake TLS Handshake — time to complete the HTTPS encryption handshake.
3 ms
Time to First Byte Time to First Byte — how long the server takes to respond with the first byte of data.
147 ms
Total Time Total request time from DNS lookup through full response.
148 ms

Connection waterfall

DNS Lookup 27 ms TCP Connect 0 ms TLS Handshake 3 ms Server Processing 116 ms Content Transfer 1 ms
A+
CDN & Delivery
Fastly (HIT, MISS, MISS, MISS)
PASS
Fastly (HIT, MISS, MISS, MISS)
Info::
Site is served via Fastly CDN
Got: x-served-by: cache-chi-kigq8000073-CHI, cache-toj-leto2350045-TOJ, cache-toj-leto2350064-TOJ, cache-toj-leto2350064-TOJ
Info::
CDN cache status: HIT, MISS, MISS, MISS
CDN Detected: Fastly
Provider Fastly Cache Status HIT, MISS, MISS, MISS Evidence x-served-by: cache-chi-kigq8000073-CHI, cache-toj-leto2350045-TOJ, cache-toj-leto2350064-TOJ, cache-toj-leto2350064-TOJ
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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