diff --git a/web/views/@default/servers/server/settings/dns/updateCNAMEPopup.html b/web/views/@default/servers/server/settings/dns/updateCNAMEPopup.html
index 84cfd082..af9094d0 100644
--- a/web/views/@default/servers/server/settings/dns/updateCNAMEPopup.html
+++ b/web/views/@default/servers/server/settings/dns/updateCNAMEPopup.html
@@ -12,7 +12,7 @@
             <td class="title">CNAME *</td>
             <td>
                 <input type="text" name="dnsName" maxlength="30" v-model="dnsName"/>
-                <p class="comment">最长只能是30个</p>
+                <p class="comment">英文字母、数字的组合，最长30个字符。</p>
             </td>
         </tr>
     </table>