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https://fu-berlin.de

Infrastructure

· 9 checks — DNS, redirects, IPv6, crawlability, URL variants, and domain intelligence rolled into one auditable list.
SCORE
86
GRADE
B
FIX
1
REVIEW
3
PASS
5
INFO
0
Probed from Madrid, Spain
301 Moved Permanently
Checks
9
5 PASS 3 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
URL Variants
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
Info::
HTTP correctly 301-redirects to HTTPS

www / non-www

200https://www.fu-berlin.de/
200https://fu-berlin.de/

Inconsistent — duplicate content risk

HTTP → HTTPS

301http://fu-berlin.de/ → https://www.fu-berlin.de/

Consistent

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

Certificate validity

182
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, 44 ms lookup
PASS
1 A records, 44 ms lookup
Info::
Resolves to 1 IPv4 address(es)
Got: 160.45.170.10
Info::
Single A record — no DNS redundancy
Multiple A records provide failover if one server goes down.
Info::
No IPv6 (AAAA) records
Info::
5 nameserver(s) configured
Got: ns1.fu-berlin.de, ns2.fu-berlin.de, atalante.stanford.edu, ns3.fu-berlin.de, dns-2.dfn.de
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: 44 ms
Got: 44 ms
A160.45.170.10
AAAA—
CNAME—
NSns1.fu-berlin.de, ns2.fu-berlin.de, atalante.stanford.edu, ns3.fu-berlin.de, dns-2.dfn.de
MX
10 mail.fu-berlin.de
TXT
SPF v=spf1 include:_spf.fu-berlin.de -all
google-site-verification=PHjgp6on3_FOQukeeiSYVvb-bxEFoh9nfJ8XRXnPtIw
CAALookup not available with standard resolver
Resolved in 44 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
1 redirect(s), 675 ms total
PASS
1 redirect(s), 675 ms total
Info::
Single redirect
Got: https://fu-berlin.de → https://www.fu-berlin.de/ (301)
Info::
WWW normalization redirect
Info::
Redirect overhead: 675 ms total
Got: 675 ms

https://fu-berlin.de

188 ms · HTTP/1.1

301

https://www.fu-berlin.de/

487 ms · HTTP/1.1 FINAL

#URLStatusTimeProtocolServer
1https://fu-berlin.de301188 msHTTP/1.1Apache
2https://www.fu-berlin.de/200487 msHTTP/1.1Apache

See the visual redirect chain in the HTTP Probe tab →

A+
Crawlability
robots.txt present, sitemap with 199 URLs
PASS
robots.txt present, sitemap with 199 URLs
Info::
robots.txt is present
Got: 787 bytes
Info::
sitemap.xml is present
Info::
sitemap.xml is valid XML
Info::
sitemap.xml contains 199 entries
Info::
Sitemap index with 199 child sitemaps
Info::
robots.txt references sitemap
robots.txt 200 OK
Size 787 B Sitemaps referenced 1 User-agents * Blocking No — crawling allowed
# See http://www.robotstxt.org/wc/norobots.html for documentation on how to use the robots.txt file
#
# To ban all spiders from the entire site uncomment the next two lines:
# User-Agent: *
# Disallow: /
# site: fu-berlin


User-agent: *
Disallow: /_search
Disallow: /en/_search
Disallow: /campusleben/_search
Disallow: /sites/weiterbildung/_search
Disallow: /en/sites/drs/_search
Disallow: /sites/drs/_search
Disallow: /sites/ggm/verwertung_entsorgung/fundgrube/_search
Disallow: /sites/forschungsdatenmanagement/_search
Disallow: /sites/genome-editing/_search
Disallow: /sites/nachhaltigkeit/_search
Disallow: /sites/ggm/verwertung_entsorgung/_search
Disallow: /en/sites/forschungsdatenmanagement/_search
Disallow: /sites/eventn/_search

Sitemap: https://www.fu-berlin.de/sitemap.xml
sitemap.xml 200 OK
Type Sitemap Index URLs 199 entries Valid XML Yes
Child Sitemaps:
A+
Domain Intelligence
fu-berlin.de — hosted on DFN Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE
PASS
fu-berlin.de — hosted on DFN Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE
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: DFN Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE
Got: AS680
Domain expiry

Unknown

SSL certificate

182 days

Issued by Hellenic Academic and Research Institutions CA

Domain age

Unknown

DNSSEC

Status unknown

Protects against DNS spoofing

Hosting

DFN Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE

ASN AS680

160.45.170.10

Registrar

Registrar unknown

Unlocked Name servers unknown
Expiry timeline
Today
+1 year
SSL expiry Danger zone (≤30 days)
Recommended actions
  • Enable registrar lock (clientTransferProhibited) to block unauthorized domain transfers
Registrar
Hosting
IP Address 160.45.170.10
ASN AS680 (DFN Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE)
Provider DFN Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE
Data source: whois (0.6s)

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

Connection waterfall

DNS Lookup 43 ms TCP Connect 36 ms TLS Handshake 168 ms Server Processing 37 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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