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https://muni.cz

Infrastructure

· 9 checks — DNS, redirects, IPv6, crawlability, URL variants, and domain intelligence rolled into one auditable list.
SCORE
82
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

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.muni.cz/
200https://muni.cz/

Inconsistent — duplicate content risk

HTTP → HTTPS

302http://muni.cz/ → https://webcentrum.muni.cz/redakce/api/RedirectsApi/SafeRedirect?host=muni.cz&path=

Use 301 (permanent) instead of 302 (temporary)

B
TLS Certificate Expiry & Recommendations
40 days until leaf cert expires — 2 issues to address
REVIEW

Certificate validity

40
days left
0d 30d 60d 90d+

Recommended actions

  • Enable HSTS: Strict-Transport-Security: max-age=31536000; includeSubDomains
  • Enable OCSP stapling on your TLS server to remove a CA roundtrip and protect user privacy
A+
DNS Records
1 A records, 68 ms lookup
PASS
1 A records, 68 ms lookup
Info::
Resolves to 1 IPv4 address(es)
Got: 147.251.5.239
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: ns2.muninet.cz, ns.muni.cz, nsa.ces.net, ns2.muni.cz
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: 68 ms
Got: 68 ms
A147.251.5.239
AAAA—
CNAME—
NSns2.muninet.cz, ns.muni.cz, nsa.ces.net, ns2.muni.cz
MX
50 relay.muni.cz
TXT
atlassian-sending-domain-verification=54f720d3-cbcd-420b-ae33-9fcedb78ab54
google-site-verification=ftbJc_Whlu5o5bA5VYCNcVPJ195FrL1gkVQNwQUATLU
SPF v=spf1 ip4:147.251.4.0/26 ip4:147.251.48.3 ip4:147.251.49.6 ip4:147.251.49.7 inc...
status-page-domain-verification=xxx37pp3swrw
atlassian-domain-verification=HiD6B1jQ7/Dlw6gabcWmGD6ZYZ2r9ugxcBB1KI594kZw89yTjN...
MS=ms85476152
CAALookup not available with standard resolver
Resolved in 68 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), 519 ms total
PASS
1 redirect(s), 519 ms total
Info::
Single redirect
Got: https://muni.cz → https://www.muni.cz/ (301)
Info::
WWW normalization redirect
Info::
Redirect overhead: 519 ms total
Got: 519 ms

https://muni.cz

122 ms · HTTP/1.1

301

https://www.muni.cz/

397 ms · HTTP/1.1 FINAL

#URLStatusTimeProtocolServer
1https://muni.cz301122 msHTTP/1.1Microsoft-IIS/10.0
2https://www.muni.cz/200397 msHTTP/1.1

See the visual redirect chain in the HTTP Probe tab →

A
Crawlability
robots.txt present, no sitemap
PASS
robots.txt present, no sitemap
Info::
robots.txt is present
Got: 152 bytes
Info::
No sitemap.xml found
A sitemap helps search engines discover and index your pages more efficiently.
Info::
robots.txt references 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

robots.txt 200 OK
Size 152 B Sitemaps referenced 1 User-agents facebookexternalhit, * Blocking No — crawling allowed
User-agent: facebookexternalhit

Disallow: /system/

Allow: /


User-agent: *

Disallow: /system/

Allow: /


Sitemap: https://www.muni.cz/sitemap.xml
sitemap.xml No sitemap found

No sitemap found

Adding a sitemap helps search engines discover your pages.

A+
Domain Intelligence
muni.cz — via REG-INTERNET-CZ, 31 years, 1 months old, hosted on CESNET2, CZ
PASS
muni.cz — via REG-INTERNET-CZ, 31 years, 1 months old, hosted on CESNET2, CZ
Info::
Domain registered until Oct 26, 2026 (6 months remaining)
Info::
DNSSEC is enabled
Info::
Registrar: REG-INTERNET-CZ
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: CESNET2, CZ
Got: AS2852
Domain expiry

102 days

October 26, 2026

SSL certificate

40 days

Issued by Let's Encrypt

Domain age

31 years, 1 months

Registered August 25, 1995

DNSSEC

Enabled

Protects against DNS spoofing

Hosting

CESNET2, CZ

ASN AS2852

147.251.5.239

Registrar

REG-INTERNET-CZ

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 REG-INTERNET-CZ
Created August 25, 1995 (31 years, 1 months ago)
Expires October 26, 2026 (6 months)
Last Updated April 24, 2025
Name Servers ns2.muni.cz, ns2.muninet.cz, nsa.ces.net, ns.muni.cz
DNSSEC Enabled
Hosting
IP Address 147.251.5.239
ASN AS2852 (CESNET2, CZ)
Provider CESNET2, CZ
Data source: rdap (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 161 ms — DNS, TCP, TLS, TTFB, content transfer breakdown
PASS
DNS Lookup DNS Lookup — time to resolve the domain name to an IP address.
39 ms
TCP Connect TCP Connect — time to establish a TCP connection to the server.
37 ms
TLS Handshake TLS Handshake — time to complete the HTTPS encryption handshake.
43 ms
Time to First Byte Time to First Byte — how long the server takes to respond with the first byte of data.
161 ms
Total Time Total request time from DNS lookup through full response.
161 ms

Connection waterfall

DNS Lookup 39 ms TCP Connect 37 ms TLS Handshake 43 ms Server Processing 41 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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