Infrastructure
· 9 checks — DNS, redirects, IPv6, crawlability, URL variants, and domain intelligence rolled into one auditable list.DCDN & DeliveryActionNo CDN detectedFIX
Consider using a CDN to improve global delivery speed and reduce origin load.
CIPv6 ReadinessActionNo IPv6 supportREVIEW
IPv6 support is increasingly important for global accessibility. About 40% of internet users have IPv6 connectivity.
No AAAA records — same impact as 'no IPv6 (AAAA) records'; IPv6-preferring clients pay extra latency falling back to IPv4.
Source: Google IPv6 stats
BCrawlabilityno robots.txt, no sitemapREVIEW
robots.txt is optional but recommended. It tells search engine crawlers which pages to index.
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.
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
No robots.txt found
This is fine for most sites — a missing robots.txt allows all crawling by default.
No sitemap found
Adding a sitemap helps search engines discover your pages.
BURL Variantswww/non-www, trailing slash, HTTP→HTTPSREVIEW
www / non-www
HTTP → HTTPS
HTTP version does not redirect to HTTPS
BTLS Certificate Expiry & Recommendations132 days until leaf cert expires — 4 issues to addressREVIEW
Certificate validity
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 Records1 A records, 158 ms lookupPASS
| A | 117.89.29.19 |
| AAAA | — |
| CNAME | — |
| NS | ns1.chinanet.cn, ns2.chinanet.cn |
| MX | 10 mta-189.21cn.com 20 mx2-189.21cn.com 30 mx3-189.21cn.com |
| TXT | b3d973d953124f18b572c0b2775d1eee d6baa51391750005fce703030c1306562566d86135d518bd4bf0b10b3d99261f google-site-verification=fnhC9eZ-Dmna-6EIvU0mJXk52k0A5TChiQaulg-xdss globalsign-domain-verification=aF1WppYM23EmniP08To6CoRhshTaAUbFJIFOs1q7VY SPF v=spf1 include:mail-spf.21cn.com include:hwmail-spf.21cn.com -all |
| CAA | Lookup not available with standard resolver |
Multiple A records provide failover if one server goes down.
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.
Informational: CAA (Certification Authority Authorization) records weren't checked in this scan.
A+Redirect Chain0 redirect(s), 758 ms totalPASS
https://189.cn
758 ms · HTTP/1.1 FINAL
| # | URL | Status | Time | Protocol | Server |
|---|---|---|---|---|---|
| 1 | https://189.cn | 412 | 758 ms | HTTP/1.1 | CTYun LB |
A+Domain Intelligence189.cn — via 阿里云计算有限公司（万网）, 22 years, 3 months old, hosted on CHINANET-NANJING-JISHAN-IDC CHINANET Nanjing Jishan IDC network, CNPASS
656 days
May 4, 2028
132 days
Issued by DigiCert, Inc.
22 years, 3 months
Registered May 4, 2004
Status unknown
Protects against DNS spoofing
CHINANET-NANJING-JISHAN-IDC CHINANET Nanjing Jishan IDC network, CN
ASN AS134756
117.89.29.19
阿里云计算有限公司（万网）
Expiry timeline
Recommended actions
- Enable registrar lock (clientTransferProhibited) to block unauthorized domain transfers
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.
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