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
BTLS Certificate Expiry & Recommendations233 days until leaf cert expires — 2 issues to addressREVIEW
Certificate validity
Recommended actions
- Add the preload directive and submit to hstspreload.org once max-age + includeSubDomains are in place
- Enable OCSP stapling on your TLS server to remove a CA roundtrip and protect user privacy
ADNS Records1 A records, 560 ms lookupPASS
| A | 52.232.69.102 |
| AAAA | — |
| CNAME | — |
| NS | new-ns1.vu.nl, new-ns2.vu.nl |
| MX | 0 vu-nl.mail.protection.outlook.com |
| TXT | MS=ms11195063 MS=ms33278211 Phone: +31 20 5985385 HARICA-2AQWWJAqj5VSqkz0rOX Vrije Universiteit Amsterdam ZOOM_verify_gOlFjB0bTXauhCZZfZ0SZA 935e51b8-957b-486c-bca0-52db87534023 B8RKMH5ZV1ICEXRNIUXA04C1D4UXWARTPQE3T8PTL apple-domain-verification=CQxBk5H2cH0MlovF HO5Hae8DJUssBXMJPxF8SuoTVyO4suOdM/31NLC0WwA= Address: De Boelelaan 1105, 1081 HV Amsterdam jamf-site-verification=mTKqAuu3KFc2rfzUgyBWng bw=JD9O8B5T3N8rye1GFjQP5tlEtsH7SuVOiTWPxSNk67Kr facebook-domain-verification=z5lo4vme7tj7rz0rkrjeyw3ficdkrt google-site-verification=5wBwCtzHALiL0eFj_8LfcLtC9A0pwqF8ChcfKHGWeUg cEePUaAdUpgbDwN8y+iChaM5q/fmwZ98byweLOwQQTzlfZ7ZqiRmUZy9plWcraR+SpUS7soZ99JhnT3u... atlassian-domain-verification=4DKZByaje8L/OfqPKIBr9eFCxXWL7x17aQeSAH5OE0dv32q8PX... successfactors-site-verification=NDVmYTkwNzVjMjQ3NDgwYTRiNTZiYjM4YWY0MjUwNjE4NDE... SPF v=spf1 include:_spf.vu.nl include:spf.protection.outlook.com include:_spf.x-com... |
| 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.
Slow DNS adds latency to every page load. Consider a faster DNS provider.
DNS resolution is slow — anycast DNS providers (Cloudflare, Route 53) typically resolve <50ms globally.
Source: DNS performance benchmarks
ARedirect Chain1 redirect(s), 699 ms totalPASS
https://vu.nl
335 ms · HTTP/1.1
https://vu.nl/nl
365 ms · HTTP/1.1 FINAL
| # | URL | Status | Time | Protocol | Server |
|---|---|---|---|---|---|
| 1 | https://vu.nl | 302 | 335 ms | HTTP/1.1 | |
| 2 | https://vu.nl/nl | 200 | 365 ms | HTTP/1.1 |
See the visual redirect chain in the HTTP Probe tab →
If permanent, use 301 instead.
302 (Found) is for genuinely temporary redirects — if this redirect is permanent, switch to 301 to preserve SEO equity.
Learn more ▾ ▴
Search engines treat 302 as temporary, keeping the original URL indexed and not transferring full link equity to the destination. Use 301 (Moved Permanently) for permanent redirects (HTTP→HTTPS, www-vs-non-www, URL restructures).
Source: Google Search Central
A+Crawlabilityrobots.txt present, sitemap with 23445 URLsPASS
Add a 'Sitemap:' directive to robots.txt so search engines can discover your sitemap.
robots.txt omits Sitemap: directive — crawlers must fetch /sitemap.xml by convention; reliable but missing the explicit hint.
Source: sitemaps.org
# Sharing knowledge is the most fundamental act of friendship. Because it is a way you can give something without loosing something.
User-agent: *
Disallow: /nl/mijn-studiekeuze/
Disallow: /en/my-studychoice/
AURL Variantswww/non-www, trailing slash, HTTP→HTTPSPASS
www / non-www
Preferred variant: non-www
HTTP → HTTPS
Use 301 (permanent) instead of 302 (temporary)
A+Domain Intelligencevu.nl — via SURF B.V., 37 years, 8 months old, hosted on Microsoft AzurePASS
Unknown
233 days
Issued by Hellenic Academic and Research Institutions CA
37 years, 8 months
Registered February 15, 1989
Enabled
Protects against DNS spoofing
Microsoft Azure
ASN AS8075
52.232.69.102
SURF B.V.
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