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Infrastructure

· 9 checks — DNS, redirects, IPv6, crawlability, URL variants, and domain intelligence rolled into one auditable list.
SCORE
90
GRADE
A
FIX
1
REVIEW
2
PASS
6
INFO
0
Probed from Madrid, Spain
301 Moved Permanently
Checks
9
6 PASS 2 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
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.chalmers.se/
200https://chalmers.se/

Inconsistent — duplicate content risk

HTTP → HTTPS

307http://chalmers.se/ → https://chalmers.se/

Use 301 (permanent) instead of 302 (temporary)

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

Certificate validity

86
days left
0d 30d 60d 90d+

Recommended actions

  • 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, 358 ms lookup
PASS
1 A records, 358 ms lookup
Info::
Resolves to 1 IPv4 address(es)
Got: 129.16.225.208
Info::
Single A record — no DNS redundancy
Multiple A records provide failover if one server goes down.
Info::
Has 1 IPv6 (AAAA) record(s)
Got: 2001:6b0:2:2009::611
Info::
4 nameserver(s) configured
Got: sunic.sunet.se, ns3.chalmers.se, ns1.chalmers.se, ns2.chalmers.se
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
Warning::
DNS resolution is slow (358 ms)
Slow DNS adds latency to every page load. Consider a faster DNS provider.
Got: 358 ms
A129.16.225.208
AAAA2001:6b0:2:2009::611
CNAME—
NSsunic.sunet.se, ns3.chalmers.se, ns1.chalmers.se, ns2.chalmers.se
MX
10 chalmers-se.mail.protection.outlook.com
TXT
facebook-domain-verification=9d92s277ebot36swusg8xt09am32zh
mindmanager-verification=21d5ed4f63465e42d1177116f4cc2b85eed35edebc0a35c829f145a...
mentimeter-cbc62098-17f2-4a14-986a-fd42319f0835
UINFO: Chalmers Tekniska H�gskola (ISO-8859-1) [sv]
ZOOM_verify_VzM3LmjDRKajK0r6i4U8Nw
apple-domain-verification=MvsPYqcOzN5YzbCH
autodesk-domain-verification=Ql85fr_zPEn0Jyb0OyNf
adobe-idp-site-verification=2f08bb719e96ca4f9b05dde868ad04193eb3ace7052d0cdc1beb...
IxQ32Cp0vVZHXqLp2pA8M7ySB2BiQVcrf5ECEAXEEP25nH4PbnhVTyLDYDY3/dUH58Gt2SVA5HWpxV/0...
MS=ms47016442
UINFO: Chalmers University of Technology [en]
UINFO: Chalmers Tekniska Högskola (UTF-8) [sv]
SPF v=spf1 ip4:129.16.226.128/26 ip4:129.16.226.155 ip4:129.16.226.153 ip4:129.16.22...
HARICA-UNAwJdkNljBQp3EtETZ
UINFO: Chalmers Tekniska Hogskola [sv]
google-site-verification=oF0feLOFPGBIp7_IyITWLdXTKcGDXbc4CbPGH2qu-z8
CAALookup not available with standard resolver
Resolved in 358 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.

Slow DNS adds latency to every page load. Consider a faster DNS provider.

Why this matters

DNS resolution is slow — anycast DNS providers (Cloudflare, Route 53) typically resolve <50ms globally.

Source: DNS performance benchmarks

A
Redirect Chain
1 redirect(s), 494 ms total
PASS
1 redirect(s), 494 ms total
Info::
Single redirect
Got: https://chalmers.se → https://www.chalmers.se/ (301)
Info::
WWW normalization redirect

https://chalmers.se

143 ms · HTTP/1.1

301

https://www.chalmers.se/

351 ms · HTTP/1.1 FINAL

#URLStatusTimeProtocolServer
1https://chalmers.se301143 msHTTP/1.1nginx/1.20.1
2https://www.chalmers.se/200351 msHTTP/1.1nginx/1.20.1

See the visual redirect chain in the HTTP Probe tab →

A+
IPv6 Readiness
IPv6 reachable (46 ms)
PASS
IPv6 reachable (46 ms)
Info::
IPv6 is configured and reachable at 2001:6b0:2:2009::611
Got: 46 ms connect
IPv6 Ready
AAAA Records 2001:6b0:2:2009::611 Connection Reachable (46 ms)
A+
Crawlability
robots.txt present, sitemap with 2 URLs
PASS
robots.txt present, sitemap with 2 URLs
Info::
robots.txt is present
Got: 265 bytes
Info::
sitemap.xml is present
Info::
sitemap.xml is valid XML
Info::
sitemap.xml contains 2 entries
Info::
Sitemap index with 2 child sitemaps
Info::
robots.txt references sitemap
robots.txt 200 OK
Size 265 B Sitemaps referenced 3 User-agents * Blocking No — crawling allowed
# *
User-agent: *
Allow: /
Disallow: /sok/
Disallow: /en/search/

# Host
Host: https://www.chalmers.se

# Sitemaps
Sitemap: https://www.chalmers.se/sitemap.xml
Sitemap: https://www.chalmers.se/sitemap-0.xml
Sitemap: https://www.chalmers.se/server-sitemap-index.xml
sitemap.xml 200 OK
Type Sitemap Index URLs 2 entries Valid XML Yes
Child Sitemaps:
A+
Domain Intelligence
chalmers.se — via Loopia AB, 41 years, 10 months old
PASS
chalmers.se — via Loopia AB, 41 years, 10 months old
Info::
Domain registered until Dec 31, 2026 (8 months remaining)
Info::
Registrar: Loopia AB
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.
Domain expiry

166 days

December 31, 2026

SSL certificate

86 days

Issued by Let's Encrypt

Domain age

41 years, 10 months

Registered January 17, 1985

DNSSEC

Status unknown

Protects against DNS spoofing

Hosting

Unknown

2001:6b0:2:2009::611

Registrar

Loopia AB

Unlocked 4 NS records
Expiry timeline
Today
+1 year
Domain expiry SSL expiry Danger zone (≤30 days)
Recommended actions
  • Enable registrar lock (clientTransferProhibited) to block unauthorized domain transfers
Registrar Loopia AB
Created January 17, 1985 (41 years, 10 months ago)
Expires December 31, 2026 (8 months)
Last Updated December 1, 2025
Name Servers ns2.chalmers.se, ns3.chalmers.se, ns1.chalmers.se, sunic.sunet.se
Registrant datcha9954-00001
Hosting
IP Address 2001:6b0:2:2009::611
Data source: whois (0.5s)

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 163 ms — DNS, TCP, TLS, TTFB, content transfer breakdown
PASS
DNS Lookup DNS Lookup — time to resolve the domain name to an IP address.
21 ms
TCP Connect TCP Connect — time to establish a TCP connection to the server.
46 ms
TLS Handshake TLS Handshake — time to complete the HTTPS encryption handshake.
48 ms
Time to First Byte Time to First Byte — how long the server takes to respond with the first byte of data.
163 ms
Total Time Total request time from DNS lookup through full response.
164 ms

Connection waterfall

DNS Lookup 21 ms TCP Connect 46 ms TLS Handshake 48 ms Server Processing 48 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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