1. General Results, most used to calculate the result A name "server-daten.de" is domain, public suffix is ".de", top-level-domain is ".de", top-level-domain-type is "country-code", Country is Germany, tld-manager is "DENIC eG", num .de-domains preloaded: 8467 (complete: 210599) A Good: All ip addresses are public addresses A Good: Minimal 2 ip addresses per domain name found: server-daten.de has 2 different ip addresses (authoritative). A Good: Minimal 2 ip addresses per domain name found: www.server-daten.de has 2 different ip addresses (authoritative). A Good: Ipv4 and Ipv6 addresses per domain name found: server-daten.de has 1 ipv4, 1 ipv6 addresses A Good: Ipv4 and Ipv6 addresses per domain name found: www.server-daten.de has 1 ipv4, 1 ipv6 addresses A Good: No asked Authoritative Name Server had a timeout A Good: destination is https A Good - only one version with Http-Status 200 A Good: one preferred version: www is preferred A Good: No cookie sent via http. A Good: every cookie sent via https is marked as secure A Good: Every cookie has a SameSite Attribute with a correct value Strict/Lax/None A Excellent: All cookies (except Cloudflare __cfduid) are Prefix-Cookies:4 Cookies complete, 4 __Host-Cookies, 0 __Secure-Cookies, 0 __cfduid-Cookies (Cloudflare) A Good: every https has a Strict Transport Security Header A Good: HSTS max-age is long enough, 63072000 seconds = 730 days A Good: HSTS has includeSubdomains - directive A Good: HSTS has preload directive A Excellent: Domain is in the Google-Preload-List A Excellent: Domain is in the Mozilla/Firefox-Preload-List A HSTS-Preload-Status: Preloaded. Check https://hstspreload.org/ to learn some basics about the Google-Preload-List. A Good: All urls with http status 200/404 have a complete Content-Type header (MediaType / MediaSubType + correct charset) A http://server-daten.de/ 85.215.2.226 https://server-daten.de/ Correct redirect http - https with the same domain name A http://server-daten.de/ 2a01:238:301b::1226 https://server-daten.de/ Correct redirect http - https with the same domain name A http://www.server-daten.de/ 85.215.2.226 https://www.server-daten.de/ Correct redirect http - https with the same domain name A http://www.server-daten.de/ 2a01:238:301b::1226 https://www.server-daten.de/ Correct redirect http - https with the same domain name N https://85.215.2.226/ 85.215.2.226 Error - Certificate isn't trusted, RemoteCertificateNameMismatch N https://[2a01:0238:301b:0000:0000:0000:0000:1226]/ 2a01:238:301b::1226 Error - Certificate isn't trusted, RemoteCertificateNameMismatch A Good: More then one ip address per domain name found, checking all ip addresses the same http status and the same certificate found: Domain server-daten.de, 2 ip addresses. A Good: More then one ip address per domain name found, checking all ip addresses the same http status and the same certificate found: Domain www.server-daten.de, 2 ip addresses. Info: Checking all ip addresses of that domain without sending the hostname only one certificate found. Checking all ip addresses and sending the hostname only one certificate found. Both certificates are the same. So that domain doesn't require Server Name Indication (SNI), it's the primary certificate of that set of ip addresses.: Domain server-daten.de, 2 ip addresses, 1 different http results. Info: Checking all ip addresses of that domain without sending the hostname only one certificate found. Checking all ip addresses and sending the hostname only one certificate found. Both certificates are the same. So that domain doesn't require Server Name Indication (SNI), it's the primary certificate of that set of ip addresses.: Domain www.server-daten.de, 2 ip addresses, 1 different http results. A Good: _mta-sts TXT record found (mta-sts: Mail Transfer Agent Strict Transport Security - see RFC 8461). Domainname: _mta-sts.server-daten.de A Good: _mta-sts TXT record is valid. A Good: Subdomain mta-sts found: Subdomain-name: mta-sts.server-daten.de, ip : 85.215.2.226 A Good: Subdomain mta-sts found: Subdomain-name: mta-sts.server-daten.de, ip : 2a01:238:301b::1226 A Good: Certificate of subdomain is valid. mta-sts.server-daten.de, ip : 85.215.2.226 A Good: Certificate of subdomain is valid. mta-sts.server-daten.de, ip : 2a01:238:301b::1226 A Good: /.well-known/mta-sts.txt with http status 200 found. Complete path: https://mta-sts.server-daten.de/.well-known/mta-sts.txt - ip : 85.215.2.226 A Good: /.well-known/mta-sts.txt with http status 200 found. Complete path: https://mta-sts.server-daten.de/.well-known/mta-sts.txt - ip : 2a01:238:301b::1226 A Good: mta-sts.txt has the required names "version", "mode", "max_age". mta-sts.server-daten.de, ip : 2a01:238:301b::1226 A Good: mta-sts.txt has the required names "version", "mode", "max_age". mta-sts.server-daten.de, ip : 85.215.2.226 A Good: Minimal one mx definition found. mta-sts.server-daten.de, ip : 2a01:238:301b::1226 A Good: Minimal one mx definition found. mta-sts.server-daten.de, ip : 85.215.2.226 A Excellent: Complete and valid MTA-STS found! 2. Header-Checks (alpha, started 2022-10-23, may be buggy / incomplete) A www.server-daten.de 85.215.2.226 Content-Security-Policy Ok: Header without syntax errors found: default-src 'none'; style-src 'self' 'unsafe-inline'; img-src 'self' data:; script-src 'self'; connect-src 'self'; child-src 'self'; frame-src 'self'; frame-ancestors 'self'; base-uri 'self'; ; report-uri /-cspr.html B Info: Header-Element is deprecated. report-uri /-cspr.html A Good: default-src directive only with 'none' or 'self', additional sources are blocked. A Good: default-src without 'unsafe-inline' or 'unsave-eval'. E Bad: No form-action directive found. Use one to limit the form - action - destinations. form-action is a navigation-directive, so default-src isn't used. A Good: frame-ancestors directive found. That limits pages who are allowed to use this page in a frame / iframe / object / embed / applet. frame-ancestors is a navigation-directive, so default-src isn't used. A Good: base-uri directive found. That limits the URLs which can be used in a document's <base> element. Because it's a document directive, default-src isn't used, so an own directive is required. A Good: No object-src found, but the default-src used as fallback is defined and restricted. A Good: script-src without 'unsafe-inline' and 'unsafe-eval' found. That's the recommended configuration. A Good: script-src without * and a scheme found. A Good: script-src without data: schema found. Why is this important? The data: schema allows hidden code injection. Insert <script src='data:application/javascript;base64,YWxlcnQoJ1hTUycpOw=='></script> in your page and see what happens. A Good: frame-src without data: defined or frame-src missing and the default-src used as fallback not allows the data: schema. That blocks hidden code injection. Insert <iframe src="data:text/html;charset=utf-8;base64,PCFET0NUWVBFIGh0bWw+PGh0bWw+PGJvZHk+PHA+YmVmb3JlPHNjcmlwdCB0eXBlPSJ0ZXh0L2phdmFzY3JpcHQiPmFsZXJ0KCdYU1MnKTwvc2NyaXB0PjxwPmFmdGVyPC9ib2R5PjwvaHRtbD4="></iframe> in your page and see what happens. A X-Content-Type-Options Ok: Header without syntax errors found: nosniff A Referrer-Policy Ok: Header without syntax errors found: strict-origin A Permissions-Policy Ok: Header without syntax errors found: camera=(self) A X-Frame-Options Ok: Header without syntax errors found: SAMEORIGIN B Info: Header is deprecated. May not longer work in modern browsers. SAMEORIGIN. Better solution: Use a Content-Security-Policy Header with a frame-ancestors directive. DENY - use 'none', SAMEORIGIN - use 'self'. If you want to allow some domains to frame your page, add these urls. A X-Xss-Protection Ok: Header without syntax errors found: 1; mode=block B Info: Header is deprecated. May not longer work in modern browsers. 1; mode=block A www.server-daten.de 2a01:238:301b::1226 Content-Security-Policy Ok: Header without syntax errors found: default-src 'none'; style-src 'self' 'unsafe-inline'; img-src 'self' data:; script-src 'self'; connect-src 'self'; child-src 'self'; frame-src 'self'; frame-ancestors 'self'; base-uri 'self'; ; report-uri /-cspr.html B Info: Header-Element is deprecated. report-uri /-cspr.html A Good: default-src directive only with 'none' or 'self', additional sources are blocked. A Good: default-src without 'unsafe-inline' or 'unsave-eval'. E Bad: No form-action directive found. Use one to limit the form - action - destinations. form-action is a navigation-directive, so default-src isn't used. A Good: frame-ancestors directive found. That limits pages who are allowed to use this page in a frame / iframe / object / embed / applet. frame-ancestors is a navigation-directive, so default-src isn't used. A Good: base-uri directive found. That limits the URLs which can be used in a document's <base> element. Because it's a document directive, default-src isn't used, so an own directive is required. A Good: No object-src found, but the default-src used as fallback is defined and restricted. A Good: script-src without 'unsafe-inline' and 'unsafe-eval' found. That's the recommended configuration. A Good: script-src without * and a scheme found. A Good: script-src without data: schema found. Why is this important? The data: schema allows hidden code injection. Insert <script src='data:application/javascript;base64,YWxlcnQoJ1hTUycpOw=='></script> in your page and see what happens. A Good: frame-src without data: defined or frame-src missing and the default-src used as fallback not allows the data: schema. That blocks hidden code injection. Insert <iframe src="data:text/html;charset=utf-8;base64,PCFET0NUWVBFIGh0bWw+PGh0bWw+PGJvZHk+PHA+YmVmb3JlPHNjcmlwdCB0eXBlPSJ0ZXh0L2phdmFzY3JpcHQiPmFsZXJ0KCdYU1MnKTwvc2NyaXB0PjxwPmFmdGVyPC9ib2R5PjwvaHRtbD4="></iframe> in your page and see what happens. A X-Content-Type-Options Ok: Header without syntax errors found: nosniff A Referrer-Policy Ok: Header without syntax errors found: strict-origin A Permissions-Policy Ok: Header without syntax errors found: camera=(self) A X-Frame-Options Ok: Header without syntax errors found: SAMEORIGIN B Info: Header is deprecated. May not longer work in modern browsers. SAMEORIGIN. Better solution: Use a Content-Security-Policy Header with a frame-ancestors directive. DENY - use 'none', SAMEORIGIN - use 'self'. If you want to allow some domains to frame your page, add these urls. A X-Xss-Protection Ok: Header without syntax errors found: 1; mode=block B Info: Header is deprecated. May not longer work in modern browsers. 1; mode=block 3. DNS- and NameServer - Checks A Info:: 16 Root-climbing DNS Queries required to find all IPv4- and IPv6-Addresses of 3 Name Servers. A Info:: 16 Queries complete, 16 with IPv6, 0 with IPv4. A Good: All DNS Queries done via IPv6. A Good: Some ip addresses of name servers found with the minimum of two DNS Queries. One to find the TLD-Zone, one to ask the TLD-Zone.ns3.inwx.eu (2a02:d500::53, 45.87.158.53) Ok (4 - 8):: An average of 5.3 queries per domain name server required to find all ip addresses of all name servers. A Info:: 3 different Name Servers found: ns.inwx.de, ns2.inwx.de, ns3.inwx.eu, 3 Name Servers included in Delegation: ns.inwx.de, ns2.inwx.de, ns3.inwx.eu, 3 Name Servers included in 1 Zone definitions: ns.inwx.de, ns2.inwx.de, ns3.inwx.eu, 1 Name Servers listed in SOA.Primary: ns.inwx.de. A Good: Only one SOA.Primary Name Server found.: ns.inwx.de. A Good: SOA.Primary Name Server included in the delegation set.: ns.inwx.de. A Good: Consistency between delegation and zone. The set of NS records served by the authoritative name servers must match those proposed for the delegation in the parent zone. Ordered list of name servers: ns.inwx.de, ns2.inwx.de, ns3.inwx.eu A Good: All Name Server Domain Names have a Public Suffix. A Good: All Name Server Domain Names ending with a Public Suffix have minimal one IPv4- or IPv6 address. A Good: All Name Server ip addresses are public. A Good: Minimal 2 different name servers (public suffix and public ip address) found: 3 different Name Servers found A Good: All name servers have ipv4- and ipv6-addresses.: 3 different Name Servers found A Good: Name servers with different Top Level Domains / Public Suffix List entries found: 3 Name Servers, 2 Top Level Domains: eu, de A Good: Name Servers with different domain names found.: 2 different Domains found A Good: Name servers with different Country locations found: 3 Name Servers, 3 Countries: AT, CH, DE A Info: Ipv4-Subnet-list: 3 Name Servers, 3 different subnets (first Byte): 176., 192., 45., 3 different subnets (first two Bytes): 176.97., 192.174., 45.87., 3 different subnets (first three Bytes): 176.97.158., 192.174.68., 45.87.158. A Excellent: Every Name Server IPv4-address starts with an unique Byte. A Info: IPv6-Subnet-list: 3 Name Servers with IPv6, 2 different subnets (first block): 2001:, 2a02:, 2 different subnets (first two blocks): 2001:067c:, 2a02:d500:, 3 different subnets (first three blocks): 2001:067c:01bc:, 2001:067c:10b8:, 2a02:d500:0000:, 3 different subnets (first four blocks): 2001:067c:01bc:0000:, 2001:067c:10b8:0000:, 2a02:d500:0000:0000: A Good: Name Server IPv6 addresses from different subnets found. A Good: Nameserver supports TCP connections: 6 good Nameserver A Good: Nameserver supports Echo Capitalization: 6 good Nameserver A Good: Nameserver supports EDNS with max. 512 Byte Udp payload, message is smaller: 6 good Nameserver A Good: Nameserver has passed 10 EDNS-Checks (OP100, FLAGS, V1, V1OP100, V1FLAGS, DNSSEC, V1DNSSEC, NSID, COOKIE, CLIENTSUBNET): 6 good Nameserver A Good: All SOA have the same Serial Number A Good: CAA entries found, creating certificate is limited: letsencrypt.org is allowed to create certificates 4. Content- and Performance-critical Checks A Good: All checks /.well-known/acme-challenge/random-filename without redirects answer with the expected http status 404 - Not Found. Creating a Letsencrypt certificate via http-01 challenge should work. If it doesn't work: Check your vHost configuration (apachectl -S, httpd -S, nginx -T). Every combination of port and ServerName / ServerAlias (Apache) or Server (Nginx) must be unique. Merge duplicated entries in one vHost. If you use an IIS, extensionless files must be allowed in the /.well-known/acme-challenge subdirectory. Create a web.config in that directory. Content: <configuration><system.webServer><staticContent><mimeMap fileExtension="." mimeType="text/plain" /></staticContent></system.webServer></configuration>. If you have a redirect http ⇒ https, that's ok, Letsencrypt follows such redirects to port 80 / 443 (same or other server). There must be a certificate. But the certificate may be expired, self signed or with a not matching domain name. Checking the validation file Letsencrypt ignores such certificate errors. Trouble creating a certificate? Use https://community.letsencrypt.org/ to ask. A Good: Every https result with status 200 supports GZip. A Good: Every https result with status 200 has a minified Html-Content with a quota lower then 110 %. A Good: Every https connection via port 443 supports the http/2 protocol via ALPN. A Good: All script Elements (type text/javascript) and src-Attribute have a defer / async - Attribute. So loading and executing these JavaScripts doesn't block parsing and rendering the Html-Output. A Good: All CSS / JavaScript files are sent with GZip. That reduces the content of the files. 4 external CSS / JavaScript files found A Good: All images with internal compression not sent via GZip. Images (.png, .jpg) are already compressed, so an additional GZip isn't helpful. 2 images (type image/png, image/jpg) found without additional GZip. Not required because these images are already compressed A Good: All CSS / JavaScript files are sent with a long Cache-Control header (minimum 7 days). So the browser can re-use these files, no download is required. 4 external CSS / JavaScript files with long Cache-Control max-age found A Good: All images are sent with a long Cache-Control header (minimum 7 days). So the browser can reuse these files, no download is required. 2 image files with long Cache-Control max-age found A Good: All checked attribute values are enclosed in quotation marks (" or '). A Good: All img-elements have a valid alt-attribute.: 2 img-elements found. A Good: Domainname is not on the "Specially Designated Nationals And Blocked Persons List" (SDN). That's an US-list of individuals and companies owned or controlled by, or acting for or on behalf of, targeted countries. It also lists individuals, groups, and entities, such as terrorists and narcotics traffickers designated under programs that are not country-specific. Collectively, such individuals and companies are called "Specially Designated Nationals" or "SDNs." Their assets are blocked and U.S. persons are generally prohibited from dealing with them. So if a domain name is on that list, it's impossible to create a Letsencrypt certificate with that domain name. Check the list manual - https://www.treasury.gov/resource-center/sanctions/sdn-list/pages/default.aspx A Duration: 452833 milliseconds, 452.833 seconds