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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
1
REVIEW
3
PASS
4
INFO
1
Probed from New York, United Stated
301 Moved Permanently
Checks
9
4 PASS 3 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.

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

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.zotero.org/
200https://zotero.org/

Inconsistent — duplicate content risk

HTTP → HTTPS

301http://zotero.org/ → https://zotero.org:443/

Consistent

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

Certificate validity

193
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
3 A records, 31 ms lookup
PASS
3 A records, 31 ms lookup
Info::
Resolves to 3 IPv4 address(es)
Got: 100.55.186.35, 54.210.192.255, 98.85.30.18
Info::
No IPv6 (AAAA) records
Info::
4 nameserver(s) configured
Got: ns-1395.awsdns-46.org, ns-1678.awsdns-17.co.uk, ns-496.awsdns-62.com, ns-635.awsdns-15.net
Info::
1 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: 31 ms
Got: 31 ms
A100.55.186.35, 54.210.192.255, 98.85.30.18
AAAA—
CNAME—
NSns-1395.awsdns-46.org, ns-1678.awsdns-17.co.uk, ns-496.awsdns-62.com, ns-635.awsdns-15.net
MX
10 mail.zotero.org
TXT
SPF v=spf1 mx include:amazonses.com -all
CAALookup not available with standard resolver
Resolved in 31 ms

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), 121 ms total
PASS
1 redirect(s), 121 ms total
Info::
Single redirect
Got: https://zotero.org → https://www.zotero.org/ (301)
Info::
WWW normalization redirect

https://zotero.org

47 ms · HTTP/1.1

301

https://www.zotero.org/

74 ms · HTTP/1.1 FINAL

#URLStatusTimeProtocolServer
1https://zotero.org30147 msHTTP/1.1Apache/2.4.65 ()
2https://www.zotero.org/20074 msHTTP/1.1Apache/2.4.65 ()

See the visual redirect chain in the HTTP Probe tab →

A+
Crawlability
robots.txt present, sitemap with 5 URLs
PASS
robots.txt present, sitemap with 5 URLs
Info::
robots.txt is present
Got: 120 bytes
Info::
sitemap.xml is present
Info::
sitemap.xml is valid XML
Info::
sitemap.xml contains 5 entries
Info::
robots.txt does not reference a sitemap
Add a 'Sitemap:' directive to robots.txt so search engines can discover your sitemap.

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 120 B Sitemaps referenced 0 User-agents * Blocking No — crawling allowed
User-agent: *
Disallow: /trac/
Disallow: /people/
Disallow: /*/following
Disallow: /*/followers
Disallow: /google-docs/
sitemap.xml 200 OK
Type URL Set URLs 5 entries Valid XML Yes
Sample URLs:
A+
HTTP Probe Timing
Total 56 ms — DNS, TCP, TLS, TTFB, content transfer breakdown
PASS
DNS Lookup DNS Lookup — time to resolve the domain name to an IP address.
32 ms
TCP Connect TCP Connect — time to establish a TCP connection to the server.
7 ms
TLS Handshake TLS Handshake — time to complete the HTTPS encryption handshake.
8 ms
Time to First Byte Time to First Byte — how long the server takes to respond with the first byte of data.
57 ms
Total Time Total request time from DNS lookup through full response.
57 ms

Connection waterfall

DNS Lookup 32 ms TCP Connect 7 ms TLS Handshake 8 ms Server Processing 9 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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