1. General Results, most used to calculate the result A name "seafile.imoskvin.com" is subdomain, public suffix is ".com", top-level-domain is ".com", top-level-domain-type is "generic", tld-manager is "VeriSign Global Registry Services", num .com-domains preloaded: 85538 (complete: 220007) A Good: All ip addresses are public addresses Warning: Only one ip address found: seafile.imoskvin.com has only one ip address. Warning: No ipv6 address found. Ipv6 is the future with a lot of new features. So every domain name should have an ipv6 address. See https://en.wikipedia.org/wiki/IPv6: seafile.imoskvin.com has no ipv6 address. A Good: No asked Authoritative Name Server had a timeout A DNS: "Name Error" means: No www-dns-entry defined. This isn't a problem A https://seafile.imoskvin.com/ 69.212.60.112 https://seafile.imoskvin.com/accounts/login/?next=/ Correct redirect https to https A Good: destination is https A Good - only one version with Http-Status 200 A Good: one preferred version: non-www is preferred A Good: No cookie sent via http. A Good: Every cookie has a SameSite Attribute with a correct value Strict/Lax/None A Good: HSTS has preload directive Warning: HSTS preload sent, but not in Preload-List. Never send a preload directive if you don't know what preload means. Check https://hstspreload.org/ to learn the basics about the Google-Preload list. If you send a preload directive, you should **immediately** add your domain to the HSTS preload list via https://hstspreload.org/ . If Google accepts the domain, so the status is "pending": Note that new entries are hardcoded into the Chrome source code and can take several months before they reach the stable version. So you will see this message some months. If you don't want that or if you don't understand "preload", but if you send a preload directive and if you have correct A-redirects, everybody can add your domain to that list. Then you may have problems, it's not easy to undo that. So if you don't want your domain preloaded, remove the preload directive. HSTS-Preload-Status: unknown. Domain never included in the Preload-list. Check https://hstspreload.org/ to learn some basics about the Google-Preload-List. A Good: Some urls with http status 200/404 have a complete Content-Type header (MediaType / MediaSubType + correct charset):2 complete Content-Type - header (3 urls) https://69.212.60.112/ 69.212.60.112 Url with incomplete Content-Type - header - missing charset A http://seafile.imoskvin.com/ 69.212.60.112 https://seafile.imoskvin.com/ Correct redirect http - https with the same domain name B Warning: HSTS max-age is too short - minimum 31536000 = 365 days required, 15768000 seconds = 182 days found B https://seafile.imoskvin.com/accounts/login/?next=/ sfcsrftoken=fBXM7zJReV7u94Maxa2e4YAHP4DuUPCDI6INoxyeCobHeukVZL8pMEaXgA1scgI7; expires=Sat, 16 Mar 2024 22:14:55 GMT; Max-Age=31449600; Path=/; SameSite=Lax Cookie sent via https, but not marked as secure B https://seafile.imoskvin.com/accounts/login/?next=/ sessionid=e3ogw9gunyzkwd7rzeavzcu54q9fxmtd; expires=Sun, 19 Mar 2023 22:14:55 GMT; HttpOnly; Max-Age=86400; Path=/; SameSite=Lax Cookie sent via https, but not marked as secure I https://seafile.imoskvin.com/accounts/login/?next=/ Content problems or problems with resources included - http links, files doesn't exist, different Content-Type definitions. Check the Html-Content - Part. N https://seafile.imoskvin.com/ 69.212.60.112 https://seafile.imoskvin.com/accounts/login/?next=/ Error - Certificate isn't trusted, RemoteCertificateNameMismatch, RemoteCertificateChainErrors N https://seafile.imoskvin.com/accounts/login/?next=/ Error - Certificate isn't trusted, RemoteCertificateNameMismatch, RemoteCertificateChainErrors N https://seafile.imoskvin.com/.well-known/acme-challenge/check-your-website-dot-server-daten-dot-de Error - Certificate isn't trusted, RemoteCertificateNameMismatch, RemoteCertificateChainErrors N https://69.212.60.112/ 69.212.60.112 Error - Certificate isn't trusted, RemoteCertificateNameMismatch, RemoteCertificateChainErrors 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 seafile.imoskvin.com, 1 ip addresses, 1 different http results. B No _mta-sts TXT record found (mta-sts: Mail Transfer Agent Strict Transport Security - see RFC 8461). Read the result of server-daten.de (Url-Checks, Comments, Connections and DomainServiceRecords) to see a complete definition. Domainname: _mta-sts.seafile.imoskvin.com 2. Header-Checks F seafile.imoskvin.com Content-Security-Policy Critical: Missing Header: F seafile.imoskvin.com X-Content-Type-Options Critical: Missing Header: F seafile.imoskvin.com Referrer-Policy Critical: Missing Header: F seafile.imoskvin.com Permissions-Policy Critical: Missing Header: 3. DNS- and NameServer - Checks A Info:: 22 Root-climbing DNS Queries required to find all IPv4- and IPv6-Addresses of 2 Name Servers. A Info:: 22 Queries complete, 22 with IPv6, 0 with IPv4. A Good: All DNS Queries done via IPv6. Bad (greater 8):: An average of 11.0 queries per domain name server required to find all ip addresses of all name servers. A Info:: 2 different Name Servers found: dns1.registrar-servers.com, dns2.registrar-servers.com, 2 Name Servers included in Delegation: dns1.registrar-servers.com, dns2.registrar-servers.com, 2 Name Servers included in 1 Zone definitions: dns1.registrar-servers.com, dns2.registrar-servers.com, 1 Name Servers listed in SOA.Primary: dns1.registrar-servers.com. A Good: Only one SOA.Primary Name Server found.: dns1.registrar-servers.com. A Good: SOA.Primary Name Server included in the delegation set.: dns1.registrar-servers.com. 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 Info: Ipv4-Subnet-list: 2 Name Servers, 1 different subnets (first Byte): 156., 1 different subnets (first two Bytes): 156.154., 2 different subnets (first three Bytes): 156.154.132., 156.154.133. A Good: Name Server IPv4-addresses from different subnet found: A Info: IPv6-Subnet-list: 2 Name Servers with IPv6, 1 different subnets (first block): 2610:, 1 different subnets (first two blocks): 2610:00a1:, 2 different subnets (first three blocks): 2610:00a1:1024:, 2610:00a1:1025:, 2 different subnets (first four blocks): 2610:00a1:1024:0000:, 2610:00a1:1025:0000: A Good: Name Server IPv6 addresses from different subnets found. A Good: Nameserver supports TCP connections: 8 good Nameserver A Good: Nameserver supports Echo Capitalization: 8 good Nameserver A Good: Nameserver supports EDNS with max. 512 Byte Udp payload, message is smaller: 8 good Nameserver A Good: Nameserver has passed 10 EDNS-Checks (OP100, FLAGS, V1, V1OP100, V1FLAGS, DNSSEC, V1DNSSEC, NSID, COOKIE, CLIENTSUBNET): 8 good Nameserver Nameserver doesn't pass all EDNS-Checks: dns1.registrar-servers.com: OP100: no result. FLAGS: no result. V1: no result. V1OP100: no result. V1FLAGS: no result. DNSSEC: no result. V1DNSSEC: no result. NSID: no result. COOKIE: no result. CLIENTSUBNET: no result. A Good: All SOA have the same Serial Number Warning: No CAA entry with issue/issuewild found, every CAA can create a certificate. Read https://en.wikipedia.org/wiki/DNS_Certification_Authority_Authorization to learn some basics about the idea of CAA. Your name server must support such an entry. Not all dns providers support CAA entries. 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. https://seafile.imoskvin.com/accounts/login/?next=/ Warning: https result with status 200 and size greater then 1024 Bytes without GZip found. Add GZip support so the html content is compressed. https://seafile.imoskvin.com/accounts/login/?next=/ Warning: Https + http status 200 + Inline CSS / JavaScript found. Don't use inline CSS / JavaScript. These are compiled and re-used ressources, save these with a long Cache-Control max-age - header. https://69.212.60.112/ 69.212.60.112 Warning: Https + http status 200 + Inline CSS / JavaScript found. Don't use inline CSS / JavaScript. These are compiled and re-used ressources, save these with a long Cache-Control max-age - header. https://seafile.imoskvin.com/accounts/login/?next=/ Warning: Https result with status 200 found, Html-Content is too big. Should be max. 110 %. May contain inline CSS / JavaScript, too much comments or white space. Re-used ressources - create files with a long Cache-Control max-age header. Remove comments and white space. https://69.212.60.112/ 69.212.60.112 Warning: Https result with status 200 found, Html-Content is too big. Should be max. 110 %. May contain inline CSS / JavaScript, too much comments or white space. Re-used ressources - create files with a long Cache-Control max-age header. Remove comments and white space. A Good: Every https connection via port 443 supports the http/2 protocol via ALPN. https://seafile.imoskvin.com/accounts/login/?next=/ Critical: Some script Elements (type text/javascript) with a src-Attribute don't have a defer / async - Attribute. Loading and executing these JavaScripts blocks parsing and rendering the Html-Output. That's bad if your site is large or the connection is slow / mobile usage. Use "async" if the js file has only functions (so nothing is executed after parsing the file) or is independend. Use "defer" if the order of the scripts is important. All "defer" scripts are executed before the DOMContentLoaded event is fired. Check https://developer.mozilla.org/en-US/docs/Web/HTML/Element/script to see some details.: 4 script elements without defer/async. https://seafile.imoskvin.com/.well-known/acme-challenge/check-your-website-dot-server-daten-dot-de Critical: Some script Elements (type text/javascript) with a src-Attribute don't have a defer / async - Attribute. Loading and executing these JavaScripts blocks parsing and rendering the Html-Output. That's bad if your site is large or the connection is slow / mobile usage. Use "async" if the js file has only functions (so nothing is executed after parsing the file) or is independend. Use "defer" if the order of the scripts is important. All "defer" scripts are executed before the DOMContentLoaded event is fired. Check https://developer.mozilla.org/en-US/docs/Web/HTML/Element/script to see some details.: 4 script elements without defer/async. Warning: CSS / JavaScript found without GZip support. Send these ressources with GZip. 14 external CSS / JavaScript files without GZip found - 0 with GZip, 14 complete 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 Warning: CSS / JavaScript files with a missing or too short Cache-Control header found. Browsers should cache and re-use these files. 14 external CSS / JavaScript files without Cache-Control-Header, 0 with Cache-Control, but no max-age, 0 with Cache-Control max-age too short (minimum 7 days), 0 with Cache-Control long enough, 14 complete. Warning: Images with a missing or too short Cache-Control header found. Browsers should cache and re-use these files. 2 image files without Cache-Control-Header, 0 with Cache-Control, but no max-age, 0 with Cache-Control max-age too short (minimum 7 days), 0 with Cache-Control long enough, 2 complete. 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 https://seafile.imoskvin.com/.well-known/acme-challenge/check-your-website-dot-server-daten-dot-de 3.853 seconds Warning: 404 needs more then one second A Duration: 278637 milliseconds, 278.637 seconds