doc: update document

en/docs/config/ad-block.md

@@ -63,7 +63,7 @@ The community provides regularly updated ad-blocking list files for SmartDNS. Yo
 
 For non-SmartDNS data, simple shell commands can convert it.
 
-### `hosts` Format
+### hosts Format
 
 The following command converts the `/path/to/hosts/file` file (replace the path with your actual file) to the format supported by SmartDNS:
 
@@ -71,7 +71,7 @@ The following command converts the `/path/to/hosts/file` file (replace the path
 cat /path/to/hosts/file | grep -v "^#" | awk '{print "address /"$2"/#"}' > anti-ad-smartdns.conf
 ```
 
-### `dnsmasq` Format
+### dnsmasq Format
 
 The dnsmasq format is similar to SmartDNS, but not compatible. You can convert it using the following command:
 

en/docs/config/block-ipv6.md

@@ -19,15 +19,21 @@ Currently, IPV6 has entered thousands of households. However, in some cases, IPV
     address /example.com/#6
     ```
 
+1. Method 3: If you need to disable IPV6 queries for a specific query port (such as the second DNS), you can configure it as follows:
+
+    ```shell
+    bind :53 -force-aaaa-soa
+    ```
+
 ## Disable Other Query Requests
 
-Smartdns supports disabling other query requests, and the corresponding parameter is `force-qtype-SOA`.
+1. Smartdns supports disabling other query requests, and the corresponding parameter is `force-qtype-SOA`.
 
-```shell
-force-qtype-SOA 28
-```
+    ```shell
+    force-qtype-SOA 28
+    ```
 
-After force-qtype-SOA parameter is the type of DNS. The specific types can be queried from the IANA Explanation.
+    After force-qtype-SOA parameter is the type of DNS. The specific types can be queried from the IANA Explanation.
 
 ## Additional Notes
 

en/docs/config/server-config.md

@@ -72,3 +72,26 @@ Currently, smartdns provides three server modes: UDP, TCP, and DOT.
     ```shell
     tcp-idle-time 120
     ```
+
+## Second DNS Server
+
+In addition to supporting basic service, the `bind-*` parameter also supports more additional features, which can be used as a special second DNS server for specific needs. The corresponding functions that can be enabled are:
+
+1. Configuration example:
+
+    ```shell
+    bind :53 -no-rule-addr -no-speed-check -no-cache
+    ```
+
+1. Parameter introduction:
+
+   | Parameter | Function                                  |
+   | --------- | ---------------------------------------- |
+   | `-no-rule-addr` | Skip address rules                  |
+   | `-no-rule-nameserver` | Skip Nameserver rules           |
+   | `-no-rule-ipset` | Skip ipset and nftset rules         |
+   | `-no-rule-soa` | Skip SOA(#) rules                      |
+   | `-no-dualstack-selection` | Disable dual-stack speed test |
+   | `-no-speed-check` | Disable speed test                       |
+   | `-no-cache` | Stop caching                               |
+   | `-force-aaaa-soa` | Disable IPV6 queries                |