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Infrastructure

· 9 checks — DNS, redirects, IPv6, crawlability, URL variants, and domain intelligence rolled into one auditable list.
SCORE
90
GRADE
A
FIX
1
REVIEW
2
PASS
6
INFO
0
Probed from Sao Paulo, Brazil
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.fly.io/
200https://fly.io/

Inconsistent — duplicate content risk

HTTP → HTTPS

301http://www.fly.io/ → https://www.fly.io/

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, 84 ms lookup
PASS
1 A records, 84 ms lookup
Info::
Resolves to 1 IPv4 address(es)
Got: 37.16.18.81
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: 2a09:8280:1::a:791
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: fly.io
Info::
4 nameserver(s) configured
Got: ns1077.hosted.flydns.net, ns1970.hosted.flydns.net, ns479.hosted.flydns.net, ns967.hosted.flydns.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: 84 ms
Got: 84 ms
A37.16.18.81
AAAA2a09:8280:1::a:791
CNAMEfly.io
NSns1077.hosted.flydns.net, ns1970.hosted.flydns.net, ns479.hosted.flydns.net, ns967.hosted.flydns.net
MX
1 aspmx.l.google.com
5 alt1.aspmx.l.google.com
5 alt2.aspmx.l.google.com
10 alt3.aspmx.l.google.com
10 alt4.aspmx.l.google.com
TXT
03D3122BDC
_6qhz8a8hhmv7vx0gk9eylqv9k240wu9
apple-domain-verification=mIsxYwEIYJeZOCwgSgclXPauTY3vXMKf8r6t8TGhEq4
google-site-verification=379cCwTcRnv9DSPgO7yVqbpcdQwGQFJ2I8YS_KLGhp0
google-site-verification=6-4NGHVsimTGK74KKPge726I27PuLMhCiUds9tsweGU
google-site-verification=OArdonQ-wgkSCtiZm8ot2oLIgorR5PS_r8mBIf2xGdE
status-page-domain-verification=45m41jq1lznf
stripe-verification=8590be7414624f53382d4049d11f21b2e40b1fcd6a9c13ebee6e945cf61d...
SPF v=spf1 include:_spf.google.com include:helpscoutemail.com include:stspg-customer...
CAALookup not available with standard resolver
Resolved in 84 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.

A
Redirect Chain
1 redirect(s), 70 ms total
PASS
1 redirect(s), 70 ms total
Info::
Single redirect
Got: https://www.fly.io → https://fly.io/ (301)
Info::
WWW normalization redirect

https://www.fly.io

45 ms · HTTP/1.1

301

https://fly.io/

25 ms · HTTP/1.1 FINAL

#URLStatusTimeProtocolServer
1https://www.fly.io30145 msHTTP/1.1Fly/6df7278a (2026-04-07)
2https://fly.io/20025 msHTTP/1.1Fly/6df7278a (2026-04-07)

See the visual redirect chain in the HTTP Probe tab →

A+
IPv6 Readiness
IPv6 reachable (1 ms)
PASS
IPv6 reachable (1 ms)
Info::
IPv6 is configured and reachable at 2a09:8280:1::a:791
Got: 1 ms connect
IPv6 Ready
AAAA Records 2a09:8280:1::a:791 Connection Reachable (1 ms)
A
Crawlability
no robots.txt, sitemap with 938 URLs
PASS
no robots.txt, sitemap with 938 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 938 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.

sitemap.xml 200 OK
Type URL Set URLs 938 entries Valid XML Yes
Sample URLs:
A+
Domain Intelligence
fly.io — via MarkMonitor Inc., 22 years old
PASS
fly.io — via MarkMonitor Inc., 22 years old
Info::
Domain registered until Jul 15, 2033 (7 years, 4 months remaining)
Info::
Registrar: MarkMonitor Inc.
Domain expiry

2586 days

July 15, 2033

SSL certificate

61 days

Issued by Let's Encrypt

Domain age

22 years

Registered July 15, 2004

DNSSEC

Status unknown

Protects against DNS spoofing

Hosting

Unknown

2a09:8280:1::a:791

Registrar

MarkMonitor Inc.

Lock status unknown 4 NS records
Expiry timeline
Today
+1 year
Domain expiry SSL expiry Danger zone (≤30 days)
Registrar MarkMonitor Inc.
Created July 15, 2004 (22 years ago)
Expires July 15, 2033 (7 years, 4 months)
Last Updated November 13, 2025
Name Servers ns479.hosted.flydns.net, ns967.hosted.flydns.net, ns1077.hosted.flydns.net, ns1970.hosted.flydns.net
Registrant Fly.io, Inc
Hosting
IP Address 2a09:8280:1::a:791
Data source: whois (1.5s)
A+
HTTP Probe Timing
Total 51 ms — DNS, TCP, TLS, TTFB, content transfer breakdown
PASS
DNS Lookup DNS Lookup — time to resolve the domain name to an IP address.
19 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.
10 ms
Time to First Byte Time to First Byte — how long the server takes to respond with the first byte of data.
51 ms
Total Time Total request time from DNS lookup through full response.
51 ms

Connection waterfall

DNS Lookup 19 ms TCP Connect 0 ms TLS Handshake 10 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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