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https://denic.de

Infrastructure

· 9 checks — DNS, redirects, IPv6, crawlability, URL variants, and domain intelligence rolled into one auditable list.
SCORE
85
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.denic.de/
200https://denic.de/

Inconsistent — duplicate content risk

HTTP → HTTPS

301http://denic.de/ → https://www.denic.de/

Consistent

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

Certificate validity

63
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, 65 ms lookup
PASS
1 A records, 65 ms lookup
Info::
Resolves to 1 IPv4 address(es)
Got: 81.91.170.12
Info::
Single A record — no DNS redundancy
Multiple A records provide failover if one server goes down.
Info::
No IPv6 (AAAA) records
Info::
4 nameserver(s) configured
Got: ns3.denic.de, ns4.denic.net, ns2.denic.de, ns1.denic.de
Info::
3 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: 65 ms
Got: 65 ms
A81.91.170.12
AAAA—
CNAME—
NSns3.denic.de, ns4.denic.net, ns2.denic.de, ns1.denic.de
MX
10 mxext2.mailbox.org
10 mxext1.mailbox.org
20 mxext3.mailbox.org
TXT
miro-verification=bdea18ce07c1ee63c109bb12411e1bc252cbd2c8
SPF v=spf1 a mx ip4:81.91.161.53 ip4:81.91.161.54 ip6:2a02:568:102:211::1:16 ip6:2a0...
CAALookup not available with standard resolver
Resolved in 65 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), 261 ms total
PASS
1 redirect(s), 261 ms total
Info::
Single redirect
Got: https://denic.de → https://www.denic.de/ (301)
Info::
WWW normalization redirect

https://denic.de

99 ms · HTTP/1.0

301

https://www.denic.de/

162 ms · HTTP/1.1 FINAL

#URLStatusTimeProtocolServer
1https://denic.de30199 msHTTP/1.0BigIP
2https://www.denic.de/200162 msHTTP/1.1

See the visual redirect chain in the HTTP Probe tab →

A
Crawlability
no robots.txt, sitemap with 1 URLs
PASS
no robots.txt, sitemap with 1 URLs
Info::
No robots.txt found
robots.txt is optional but recommended. It tells search engine crawlers which pages to index.
Info::
sitemap.xml is present
Info::
sitemap.xml is valid XML
Info::
sitemap.xml contains 1 entries
Info::
Sitemap index with 1 child sitemaps

robots.txt is optional but recommended. It tells search engine crawlers which pages to index.

Why this matters

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

robots.txt No robots.txt found

No robots.txt found

This is fine for most sites — a missing robots.txt allows all crawling by default.

sitemap.xml 200 OK
Type Sitemap Index URLs 1 entries Valid XML Yes
Child Sitemaps:
A+
Domain Intelligence
denic.de — hosted on DENIC-AS Theodor-Stern-Kai 1, DE
PASS
denic.de — hosted on DENIC-AS Theodor-Stern-Kai 1, 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: DENIC-AS Theodor-Stern-Kai 1, DE
Got: AS8763
Domain expiry

Unknown

SSL certificate

63 days

Issued by Let's Encrypt

Domain age

Unknown

DNSSEC

Status unknown

Protects against DNS spoofing

Hosting

DENIC-AS Theodor-Stern-Kai 1, DE

ASN AS8763

81.91.170.12

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 81.91.170.12
ASN AS8763 (DENIC-AS Theodor-Stern-Kai 1, DE)
Provider DENIC-AS Theodor-Stern-Kai 1, DE
Data source: whois (0.8s)

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

Connection waterfall

DNS Lookup 60 ms TCP Connect 30 ms TLS Handshake 37 ms Server Processing 31 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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