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Infrastructure

· 9 checks — DNS, redirects, IPv6, crawlability, URL variants, and domain intelligence rolled into one auditable list.
SCORE
93
GRADE
A
FIX
0
REVIEW
3
PASS
5
INFO
1
Probed from Sao Paulo, Brazil
200 OK
Checks
9
5 PASS 3 REVIEW
B
DNS Records
1 A records, 60 ms lookup
REVIEW
1 A records, 60 ms lookup
Info::
Resolves to 1 IPv4 address(es)
Got: 54.232.119.62
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: 2600:1f1e:7c1:c300::258
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: redux-docs.netlify.app
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: 60 ms
Got: 60 ms
A54.232.119.62
AAAA2600:1f1e:7c1:c300::258
CNAMEredux-docs.netlify.app
NS
MX
TXT
CAALookup not available with standard resolver
Resolved in 60 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)

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

Certificate validity

66
days left
0d 30d 60d 90d+

Recommended actions

  • Add includeSubDomains to the HSTS directive
  • Add the preload directive and submit to hstspreload.org once max-age + includeSubDomains are in place
  • 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
Netlify
REVIEW
Netlify
Info::
Site is served via Netlify CDN
Got: x-nf-request-id: 01KNCWTVK3DDCE3AR0PBRJBFQ3
CDN Detected: Netlify
Provider Netlify Evidence x-nf-request-id: 01KNCWTVK3DDCE3AR0PBRJBFQ3
A+
Redirect Chain
No redirects — direct access
PASS
No redirects — direct access
Info::
No redirects — direct access
Got: https://redux.js.org

https://redux.js.org

68 ms · HTTP/1.1 FINAL

#URLStatusTimeProtocolServer
1https://redux.js.org20068 msHTTP/1.1Netlify
A+
IPv6 Readiness
IPv6 reachable (2 ms)
PASS
IPv6 reachable (2 ms)
Info::
IPv6 is configured and reachable at 2600:1f1e:7c1:c300::258
Got: 2 ms connect
IPv6 Ready
AAAA Records 2600:1f1e:7c1:c300::258 Connection Reachable (2 ms)
A
Crawlability
no robots.txt, sitemap with 87 URLs
PASS
no robots.txt, sitemap with 87 URLs
Info::
No robots.txt found
robots.txt is optional but recommended. It tells search engine crawlers which pages to index.
Info::
sitemap.xml is present
Info::
sitemap.xml is valid XML
Info::
sitemap.xml contains 87 entries

robots.txt is optional but recommended. It tells search engine crawlers which pages to index.

Why this matters

No robots.txt — crawlers fetch /robots.txt and get 404; not breaking but means default crawl behavior with no directives or sitemap reference.

Learn more

A minimal robots.txt with `User-agent: * / Allow: / / Sitemap: https://example.com/sitemap.xml` covers the basics. Without it, crawlers behave fine but lose the sitemap signal and can't be selectively blocked from crawl-traps.

Source: robotstxt.org

robots.txt No robots.txt found

No robots.txt found

This is fine for most sites — a missing robots.txt allows all crawling by default.

A+
URL Variants
www/non-www, trailing slash, HTTP→HTTPS
PASS
www/non-www, trailing slash, HTTP→HTTPS
Info::
HTTP correctly 301-redirects to HTTPS

www / non-www

https://www.redux.js.org/
200https://redux.js.org/

HTTP → HTTPS

301http://redux.js.org/ https://redux.js.org/

Consistent

A+
HTTP Probe Timing
Total 316 ms — DNS, TCP, TLS, TTFB, content transfer breakdown
PASS
DNS Lookup DNS Lookup — time to resolve the domain name to an IP address.
11 ms
TCP Connect TCP Connect — time to establish a TCP connection to the server.
2 ms
TLS Handshake TLS Handshake — time to complete the HTTPS encryption handshake.
151 ms
Time to First Byte Time to First Byte — how long the server takes to respond with the first byte of data.
316 ms
Total Time Total request time from DNS lookup through full response.
316 ms

Connection waterfall

DNS Lookup 11 ms TCP Connect 2 ms TLS Handshake 151 ms Server Processing 151 ms Content Transfer 0 ms
Domain Intelligence
Domain intelligence data not available
INFO
Domain intelligence data not available

RDAP and WHOIS lookup both failed

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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