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Infrastructure

· 9 checks — DNS, redirects, IPv6, crawlability, URL variants, and domain intelligence rolled into one auditable list.
SCORE
84
GRADE
B
FIX
0
REVIEW
4
PASS
4
INFO
1
Probed from Madrid, Spain
200 OK
Checks
9
4 PASS 4 REVIEW
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

C
Crawlability
Action
robots.txt present, sitemap with 0 URLs
REVIEW
robots.txt present, sitemap with 0 URLs
Info::
robots.txt is present
Got: 223 bytes
Info::
sitemap.xml is present
Warning::
sitemap.xml contains invalid XML
Search engines may not be able to parse the sitemap. Fix XML validation errors.
Warning::
sitemap.xml is empty — no URLs found
An empty sitemap provides no value. Add <url> entries for your pages.
Info::
robots.txt does not reference a sitemap
Add a 'Sitemap:' directive to robots.txt so search engines can discover your sitemap.

Search engines may not be able to parse the sitemap. Fix XML validation errors.

Why this matters

An unparseable sitemap is silently ignored by Google — the URLs it advertises are never queued for crawl.

Learn more

Google's sitemap parser is strict about XML validity. A single unescaped `&` or unclosed tag invalidates the whole file. Run your sitemap through a validator (Search Console's Sitemaps report flags it) and fix the offending entry. Most generators escape correctly; mistakes usually come from manually-written entries.

Source: sitemaps.org / Google Search Central

An empty sitemap provides no value. Add <url> entries for your pages.

Why this matters

An empty sitemap signals 'no content to index' to Google — actively harmful versus having no sitemap at all.

Learn more

Google compares URLs in the sitemap against URLs it has crawled. An empty sitemap on a site with thousands of pages signals abandonment. Either populate it correctly (most CMSes auto-generate) or delete the file and let Google crawl normally.

Source: Google Search Central / sitemaps.org

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 223 B Sitemaps referenced 0 User-agents PingBot, PerplexityBot, GPTBot, BaiduSpider, * Blocking No — crawling allowed
# www.robotstxt.org/

User-agent: *
Disallow: /api/*
Disallow: *?view_only=
crawl-delay: 10

# Robots that have misbehaved
User-agent: PingBot
User-agent: PerplexityBot
User-agent: GPTBot
User-agent: BaiduSpider
Disallow: *
sitemap.xml 200 OK
Type URL Set URLs 0 entries Valid XML No
B
TLS Certificate Expiry & Recommendations
77 days until leaf cert expires — 3 issues to address
REVIEW

Certificate validity

77
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
B
CDN & Delivery
Google Cloud CDN
REVIEW
Google Cloud CDN
Info::
Site is served via Google Cloud CDN CDN
Got: via: 1.1 google
CDN Detected: Google Cloud CDN
Provider Google Cloud CDN Evidence via: 1.1 google
A+
DNS Records
1 A records, 24 ms lookup
PASS
1 A records, 24 ms lookup
Info::
Resolves to 1 IPv4 address(es)
Got: 35.190.84.173
Info::
Single A record — no DNS redundancy
Multiple A records provide failover if one server goes down.
Info::
No IPv6 (AAAA) records
Info::
4 nameserver(s) configured
Got: ns-cloud-e4.googledomains.com, ns-cloud-e2.googledomains.com, ns-cloud-e3.googledomains.com, ns-cloud-e1.googledomains.com
Info::
2 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: 24 ms
Got: 24 ms
A35.190.84.173
AAAA
CNAME
NSns-cloud-e4.googledomains.com, ns-cloud-e2.googledomains.com, ns-cloud-e3.googledomains.com, ns-cloud-e1.googledomains.com
MX
10 mxa.mailgun.org
10 mxb.mailgun.org
TXT
SPF v=spf1 include:servers.mcsv.net include:mailgun.org include:spf.mandrillapp.com ...
CAALookup not available with standard resolver
Resolved in 24 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.

A+
Redirect Chain
No redirects — direct access
PASS
No redirects — direct access
Info::
No redirects — direct access
Got: https://osf.io

https://osf.io

447 ms · HTTP/1.1 FINAL

#URLStatusTimeProtocolServer
1https://osf.io200447 msHTTP/1.1nginx
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: non-www)
Info::
HTTP correctly 301-redirects to HTTPS

www / non-www

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

Preferred variant: non-www

HTTP → HTTPS

301http://osf.io/ https://osf.io/

Consistent

A+
HTTP Probe Timing
Total 168 ms — DNS, TCP, TLS, TTFB, content transfer breakdown
PASS
DNS Lookup DNS Lookup — time to resolve the domain name to an IP address.
18 ms
TCP Connect TCP Connect — time to establish a TCP connection to the server.
17 ms
TLS Handshake TLS Handshake — time to complete the HTTPS encryption handshake.
21 ms
Time to First Byte Time to First Byte — how long the server takes to respond with the first byte of data.
168 ms
Total Time Total request time from DNS lookup through full response.
168 ms

Connection waterfall

DNS Lookup 18 ms TCP Connect 17 ms TLS Handshake 21 ms Server Processing 112 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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