diff --git a/README.md b/README.md
index b6e97b9..ac8b91c 100644
--- a/README.md
+++ b/README.md
@@ -103,7 +103,8 @@ Otherwise, you can run this command to revert all changes made by the script:
  * `--ip <string>` Disable the auto network config (DHCP) and configure a static IP address, e.g. `10.0.0.2`, `1.2.3.4/24`, `2001:2345:6789:abcd::ef/48`
  * `--netmask <string>` e.g. `255.255.255.0`, `ffff:ffff:ffff:ffff::`
  * `--gateway <string>` e.g. `10.0.0.1`, `none` if no gateway
- * `--dns '8.8.8.8 8.8.4.4'` (Default IPv6 DNS: `2001:4860:4860::8888 2001:4860:4860::8844`)
+ * `--dns '8.8.8.8 8.8.4.4'`
+ * `--dns6 '2001:4860:4860::8888 2001:4860:4860::8844'` (effective only if IPv6 is specified)
  * `--hostname <string>` FQDN hostname (includes the domain name), e.g. `server1.example.com`
  * `--network-console` Enable the network console of the installer. `ssh installer@ip` to connect
  * `--version 12` Supports: `10`, `11`, `12`, `13`
@@ -170,6 +171,7 @@ Otherwise, you can run this command to revert all changes made by the script:
 ### `--ustc` | `--china`
 
  * `--dns '119.29.29.29'`
+ * `--dns6 '2402:4e00::'`
  * `--mirror-protocol https`
  * `--mirror-host mirrors.ustc.edu.cn`
  * `--security-repository mirror`
@@ -178,6 +180,7 @@ Otherwise, you can run this command to revert all changes made by the script:
 ### `--tuna`
 
  * `--dns '119.29.29.29'`
+ * `--dns6 '2402:4e00::'`
  * `--mirror-protocol https`
  * `--mirror-host mirrors.tuna.tsinghua.edu.cn`
  * `--security-repository mirror`
@@ -186,7 +189,8 @@ Otherwise, you can run this command to revert all changes made by the script:
 ### `--aliyun`
 
  * `--dns '223.5.5.5 223.6.6.6'`
+ * `--dns6 '2400:3200::1 2400:3200:baba::1'`
  * `--mirror-protocol https`
  * `--mirror-host mirrors.aliyun.com`
  * `--security-repository mirror`
- * `--ntp ntp.aliyun.com`
+ * `--ntp time.amazonaws.cn`