docs: add dns validation doc

Author: jeboehm

.mkdocs.yaml

@@ -35,6 +35,7 @@ nav:
       - administration/manage-aliases.md
       - administration/manage-fetchmail.md
       - administration/dkim-signing.md
+      - administration/dns-validation-wizard.md
   - Recipes:
       - Docker:
           - Traefik Reverse Proxy: https://github.com/jeboehm/docker-mailserver/tree/main/docs/example-configs/compose/traefik-reverse-proxy

README.md

@@ -31,6 +31,7 @@ The documentation includes:
 - Quota management, catch-all addresses, and send-only accounts
 - Restriction of sender addresses for enhanced security
 - Full-text search and enforced TLS
+- DNS Validation Wizard for all mail related DNS records
 - Continuous health monitoring
 
 See the [documentation](https://jeboehm.github.io/docker-mailserver/) for a complete feature list.

docs/administration/dns-validation-wizard.md

@@ -0,0 +1,13 @@
+# DNS Validation Wizard
+
+The DNS Validation Wizard verifies DNS configuration for domains. It checks DNS records required for mailserver operation, including MX, SPF, DKIM, and DMARC records.
+
+![DNS Validation Wizard](../images/admin/dns_wizard.png)
+
+The wizard queries DNS records and displays the validation status for each record type. It shows which records are correctly configured and which require attention.
+
+## DNS Propagation
+
+DNS changes may take time to propagate across DNS servers. Typical propagation times range from a few minutes to 48 hours, depending on TTL values and DNS provider. If the wizard shows validation failures immediately after adding or modifying DNS records, wait for propagation to complete before re-checking.
+
+For detailed information about required DNS records and their configuration, see [DNS Configuration](../configuration/dns-configuration.md).