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Infrastructure

· 9 checks — DNS, redirects, IPv6, crawlability, URL variants, and domain intelligence rolled into one auditable list.
SCORE
83
GRADE
B
FIX
1
REVIEW
4
PASS
4
INFO
0
Probed from Amsterdam, Netherlands
301 Moved Permanently
Checks
9
4 PASS 4 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
Redirect Chain
1 redirect(s), 1092 ms total
REVIEW
1 redirect(s), 1092 ms total
Info::
Single redirect
Got: https://jianshu.com → https://www.jianshu.com/ (301)
Info::
WWW normalization redirect
Warning::
Redirect overhead: 1092 ms total
Got: 1092 ms

https://jianshu.com

577 ms · HTTP/1.1

301

https://www.jianshu.com/

515 ms · HTTP/1.1 FINAL

#URLStatusTimeProtocolServer
1https://jianshu.com301577 msHTTP/1.1openresty/1.21.4.1
2https://www.jianshu.com/403515 msHTTP/1.1Tengine

See the visual redirect chain in the HTTP Probe tab →

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
Crawlability
no robots.txt, no sitemap
REVIEW
no robots.txt, no sitemap
Info::
No robots.txt found
robots.txt is optional but recommended. It tells search engine crawlers which pages to index.
Info::
No sitemap.xml found
A sitemap helps search engines discover and index your pages more efficiently.

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

A sitemap helps search engines discover and index your pages more efficiently.

Why this matters

No sitemap.xml — Google relies on crawl-graph discovery alone, slowing indexing of deep or fresh URLs.

Learn more

A sitemap accelerates Google's discovery of new and updated content. Most CMSes auto-generate one; static-site frameworks need a build-step plugin. Reference it from robots.txt and submit in Search Console to confirm Google can fetch it.

Source: sitemaps.org / Google Search Central

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 No sitemap found

No sitemap found

Adding a sitemap helps search engines discover your pages.

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

Certificate validity

201
days left
0d 30d 60d 90d+

Recommended actions

  • Prefer TLS 1.3 — TLS 1.2 is acceptable but TLS 1.3 removes RSA key exchange and improves latency
  • 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, 18 ms lookup
PASS
1 A records, 18 ms lookup
Info::
Resolves to 1 IPv4 address(es)
Got: 47.251.58.39
Info::
Single A record — no DNS redundancy
Multiple A records provide failover if one server goes down.
Info::
No IPv6 (AAAA) records
Info::
2 nameserver(s) configured
Got: vip4.alidns.com, vip3.alidns.com
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: 18 ms
Got: 18 ms
A47.251.58.39
AAAA
CNAME
NSvip4.alidns.com, vip3.alidns.com
MX
0 jianshu-com.mail.protection.partner.outlook.cn
TXT
google-site-verification=6ARJIxhZLIgZT7J8MZkENr5mR0-CqshgzYyA3r3jBWU
SPF v=spf1 include:spf.protection.partner.outlook.cn -all
MS=ms95641435
CAALookup not available with standard resolver
Resolved in 18 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+
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

403https://www.jianshu.com/
200https://jianshu.com/

HTTP → HTTPS

301http://jianshu.com/ https://www.jianshu.com/

Consistent

A+
Domain Intelligence
jianshu.com — via Alibaba Cloud Computing Ltd. d/b/a HiChina (www.net.cn), 18 years, 4 months old, hosted on Alibaba Cloud
PASS
jianshu.com — via Alibaba Cloud Computing Ltd. d/b/a HiChina (www.net.cn), 18 years, 4 months old, hosted on Alibaba Cloud
Info::
Domain registered until Jan 7, 2036 (9 years, 10 months remaining)
Info::
DNSSEC is not enabled
DNSSEC protects against DNS spoofing attacks. While not required, enabling DNSSEC adds an additional layer of security. Contact your DNS provider to enable it.
Info::
Registrar: Alibaba Cloud Computing Ltd. d/b/a HiChina (www.net.cn)
Warning::
Registrar lock is NOT enabled
The domain can be transferred without an unlock step. Enable registrar lock (clientTransferProhibited) in your registrar's control panel to protect against unauthorized or accidental transfers.
Info::
Hosting: Alibaba Cloud
Got: AS45102
Domain expiry

3492 days

January 7, 2036

SSL certificate

201 days

Issued by DigiCert Inc

Domain age

18 years, 4 months

Registered March 20, 2008

DNSSEC

Not enabled

Protects against DNS spoofing

Hosting

Alibaba Cloud

ASN AS45102

47.251.58.39

Registrar

Alibaba Cloud Computing Ltd. d/b/a HiChina (www.net.cn)

Unlocked 2 NS records
Expiry timeline
Today
+1 year
Domain expiry SSL expiry Danger zone (≤30 days)
Recommended actions
  • Enable DNSSEC to protect visitors from DNS spoofing
  • Enable registrar lock (clientTransferProhibited) to block unauthorized domain transfers
Registrar Alibaba Cloud Computing Ltd. d/b/a HiChina (www.net.cn)
Created March 20, 2008 (18 years, 4 months ago)
Expires January 7, 2036 (9 years, 10 months)
Last Updated January 7, 2026
Name Servers vip3.alidns.com, vip4.alidns.com
DNSSEC Not enabled
Hosting
IP Address 47.251.58.39
ASN AS45102 (ALIBABA-CN-NET Alibaba US Technology Co., Ltd., CN)
Provider Alibaba Cloud
Data source: rdap (0.2s)

DNSSEC protects against DNS spoofing attacks. While not required, enabling DNSSEC adds an additional layer of security. Contact your DNS provider to enable it.

Why this matters

Without DNSSEC, an attacker who can poison your DNS can hijack your domain — and SSL certs alone don't stop them.

Learn more

DNSSEC adds cryptographic signatures to DNS records, preventing forged responses from poisoning resolver caches. Without it, an attacker who controls the network path can redirect your domain to a malicious server before any HTTPS handshake happens. Most modern registrars (Cloudflare, Google Domains, Route 53) enable it with one toggle.

Source: ICANN / RFC 4033

The domain can be transferred without an unlock step. Enable registrar lock (clientTransferProhibited) in your registrar's control panel to protect against unauthorized or accidental transfers.

Why this matters

Without registrar lock, an attacker who phishes your registrar credentials can transfer the domain in minutes — total brand hijack.

Learn more

Registrar lock (clientTransferProhibited, clientUpdateProhibited, clientDeleteProhibited) requires extra verification before any transfer/update/delete. Every major registrar offers it free. Combined with 2FA on your registrar account, it's the strongest defense against domain hijacking.

Source: ICANN / domain-security best practice

A
HTTP Probe Timing
Total 574 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.
139 ms
TLS Handshake TLS Handshake — time to complete the HTTPS encryption handshake.
279 ms
Time to First Byte Time to First Byte — how long the server takes to respond with the first byte of data.
575 ms
Total Time Total request time from DNS lookup through full response.
575 ms

Connection waterfall

DNS Lookup 19 ms TCP Connect 139 ms TLS Handshake 279 ms Server Processing 139 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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