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https://cuhk.edu.hk

Infrastructure

· 9 checks — DNS, redirects, IPv6, crawlability, URL variants, and domain intelligence rolled into one auditable list.
SCORE
83
GRADE
B
FIX
1
REVIEW
5
PASS
3
INFO
0
Probed from Madrid, Spain
200 OK
Checks
9
3 PASS 5 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
Crawlability
robots.txt present, no sitemap
REVIEW
robots.txt present, no sitemap
Info::
robots.txt is present
Got: 78 bytes
Info::
No sitemap.xml found
A sitemap helps search engines discover and index your pages more efficiently.
Info::
robots.txt does not reference a sitemap
Add a 'Sitemap:' directive to robots.txt so search engines can discover your sitemap.

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

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 78 B Sitemaps referenced 0 User-agents * Blocking No — crawling allowed
User-agent:*

Disallow: /english/admissions/style/ejs.js
sitemap.xml No sitemap found

No sitemap found

Adding a sitemap helps search engines discover your pages.

C
URL Variants
Action
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
Warning::
HTTP→HTTPS redirect uses 302 instead of 301
Got: 302 temporary redirect Expected: 301 permanent redirect

www / non-www

200https://www.cuhk.edu.hk/
200https://cuhk.edu.hk/

Inconsistent — duplicate content risk

HTTP → HTTPS

302http://cuhk.edu.hk/ → https://cuhk.edu.hk/

Use 301 (permanent) instead of 302 (temporary)

B
HTTP Probe Timing
Total 1445 ms — DNS, TCP, TLS, TTFB, content transfer breakdown
REVIEW
DNS Lookup DNS Lookup — time to resolve the domain name to an IP address.
167 ms
TCP Connect TCP Connect — time to establish a TCP connection to the server.
317 ms
TLS Handshake TLS Handshake — time to complete the HTTPS encryption handshake.
641 ms
Time to First Byte Time to First Byte — how long the server takes to respond with the first byte of data.
1.45 s
Total Time Total request time from DNS lookup through full response.
1.45 s

Connection waterfall

DNS Lookup 167 ms TCP Connect 317 ms TLS Handshake 641 ms Server Processing 320 ms Content Transfer 0 ms
B
TLS Certificate Expiry & Recommendations
341 days until leaf cert expires — 4 issues to address
REVIEW

Certificate validity

341
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, 29 ms lookup
PASS
1 A records, 29 ms lookup
Info::
Resolves to 1 IPv4 address(es)
Got: 27.126.235.25
Info::
Single A record — no DNS redundancy
Multiple A records provide failover if one server goes down.
Info::
No IPv6 (AAAA) records
Info::
6 nameserver(s) configured
Got: dns2.cuhk.edu.hk, ns4.gdnsdef.com, anyns.cuhk.edu.hk, dns1.cuhk.edu.hk, ns4.gdnsec.com, dns3.cuhk.edu.hk
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: 29 ms
Got: 29 ms
A27.126.235.25
AAAA—
CNAME—
NSdns2.cuhk.edu.hk, ns4.gdnsdef.com, anyns.cuhk.edu.hk, dns1.cuhk.edu.hk, ns4.gdnsec.com, dns3.cuhk.edu.hk
MX
5 cuhk-st.in.tmes.trendmicro.com
TXT
SPF v=spf1 include:spf.protection.outlook.com include:spfe.itsc.cuhk.edu.hk include:...
google-site-verification=cGTxUZkK1PBJ2dmfxNmtS9Q3n1XNb2qwvVyQkIrq9CA
h5WA8UpWGJWDLyxQvxpOC9isc0019te/wKy9xGdID77RbUkXS9N0BgPvNtPd2KKg9JMjbG1jIUFrrrrT...
adobe-idp-site-verification=7fc23f51ce60adec0d8796a683914ba1167fb49fc42d8889fa74...
Foxit-domain-verification=7b63330972e6429e349104a11a97ec34
CAALookup not available with standard resolver
Resolved in 29 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://cuhk.edu.hk

https://cuhk.edu.hk

1329 ms · HTTP/1.1 FINAL

#URLStatusTimeProtocolServer
1https://cuhk.edu.hk2001329 msHTTP/1.1Apache
A+
Domain Intelligence
cuhk.edu.hk — via Hong Kong Domain Name Registration Company Limited, hosted on NEXUSGUARD-AS-AP Nexusguard Pte. Ltd., SG
PASS
cuhk.edu.hk — via Hong Kong Domain Name Registration Company Limited, hosted on NEXUSGUARD-AS-AP Nexusguard Pte. Ltd., SG
Info::
Registrar: Hong Kong Domain Name Registration Company Limited
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: NEXUSGUARD-AS-AP Nexusguard Pte. Ltd., SG
Got: AS45474
Domain expiry

Unknown

SSL certificate

341 days

Issued by Sectigo Limited

Domain age

Unknown

DNSSEC

Status unknown

Protects against DNS spoofing

Hosting

NEXUSGUARD-AS-AP Nexusguard Pte. Ltd., SG

ASN AS45474

27.126.235.25

Registrar

Hong Kong Domain Name Registration Company Limited

Unlocked 5 NS records
Expiry timeline
Today
+1 year
SSL expiry Danger zone (≤30 days)
Recommended actions
  • Enable registrar lock (clientTransferProhibited) to block unauthorized domain transfers
Registrar Hong Kong Domain Name Registration Company Limited
Name Servers dns1.cuhk.edu.hk, dns2.cuhk.edu.hk, anyns.cuhk.edu.hk, ns4.gdnsec.com, ns4.gdnsdef.com
Registrant THE CHINESE UNIVERSITY OF HONG KONG
Hosting
IP Address 27.126.235.25
ASN AS45474 (NEXUSGUARD-AS-AP Nexusguard Pte. Ltd., SG)
Provider NEXUSGUARD-AS-AP Nexusguard Pte. Ltd., SG
Data source: whois (2.1s)

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

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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