diff --git a/Web/Controls/Help/Server/Linux/Document/LinInstallCentOSARM/LinInstallCentOSARM.ascx b/Web/Controls/Help/Server/Linux/Document/LinInstallCentOSARM/LinInstallCentOSARM.ascx
index 5cd7ba716..2c95a011b 100644
--- a/Web/Controls/Help/Server/Linux/Document/LinInstallCentOSARM/LinInstallCentOSARM.ascx
+++ b/Web/Controls/Help/Server/Linux/Document/LinInstallCentOSARM/LinInstallCentOSARM.ascx
@@ -254,6 +254,14 @@ sudo systemctl enable nginx
     <div class="block_of_step">
         <div class="screen_text">
             <h5>Run a configuration script</h5>
+            <div class="notehelp nh_important">
+                <span class="important_notice_label">Note</span>
+                By default, PostgreSQL is used as a database. If you want to use MySQL instead of PostgreSQL, please add two environment variables for defining database type and port before running the <b>documentserver-configure.sh</b> script:
+                <pre><code>export DB_TYPE=mysql
+export DB_PORT=6443
+</code></pre>
+                <p>After adding these two variables, you will be able to switch the DB using the script.</p>
+            </div>
             <p>Run the <code>documentserver-configure.sh</code> script:</p>
             <pre><code>bash documentserver-configure.sh
 </code></pre>
diff --git a/Web/Controls/Help/Server/Linux/Document/LinuxInstallationCentOS/LinuxInstallationCentOS.ascx b/Web/Controls/Help/Server/Linux/Document/LinuxInstallationCentOS/LinuxInstallationCentOS.ascx
index 295bf1813..f87f14a3a 100644
--- a/Web/Controls/Help/Server/Linux/Document/LinuxInstallationCentOS/LinuxInstallationCentOS.ascx
+++ b/Web/Controls/Help/Server/Linux/Document/LinuxInstallationCentOS/LinuxInstallationCentOS.ascx
@@ -236,6 +236,14 @@ sudo systemctl enable nginx
     <div class="block_of_step">
         <div class="screen_text">
             <h5>Run a configuration script</h5>
+            <div class="notehelp nh_important">
+                <span class="important_notice_label">Note</span>
+                By default, PostgreSQL is used as a database. If you want to use MySQL instead of PostgreSQL, please add two environment variables for defining database type and port before running the <b>documentserver-configure.sh</b> script:
+                <pre><code>export DB_TYPE=mysql
+export DB_PORT=6443
+</code></pre>
+                <p>After adding these two variables, you will be able to switch the DB using the script.</p>
+            </div>
             <p>Run the <code>documentserver-configure.sh</code> script:</p>
             <pre><code>bash documentserver-configure.sh
 </code></pre>
diff --git a/Web/Controls/Help/Server/Linux/Document/LinuxInstallationCentOS/LinuxInstallationCentOS.ru.ascx b/Web/Controls/Help/Server/Linux/Document/LinuxInstallationCentOS/LinuxInstallationCentOS.ru.ascx
index aaaeb6f6c..4806c7160 100644
--- a/Web/Controls/Help/Server/Linux/Document/LinuxInstallationCentOS/LinuxInstallationCentOS.ru.ascx
+++ b/Web/Controls/Help/Server/Linux/Document/LinuxInstallationCentOS/LinuxInstallationCentOS.ru.ascx
@@ -236,6 +236,14 @@ sudo systemctl enable nginx
     <div class="block_of_step">
         <div class="screen_text">
             <h5>Запустите скрипт конфигурации</h5>
+            <div class="notehelp nh_important">
+                <span class="important_notice_label">Примечание</span>
+                По умолчанию в качестве базы данных используется PostgreSQL. Если вы хотите использовать MySQL вместо PostgreSQL, добавьте две переменные окружения для определения типа и порта базы данных перед тем, как запускать скрипт <b>documentserver-configure.sh</b>:
+                <pre><code>export DB_TYPE=mysql
+export DB_PORT=6443
+</code></pre>
+                <p>После добавления этих двух переменных вы сможете переключить базу данных с помощью скрипта.</p>
+            </div>
             <p>Запустите скрипт <code>documentserver-configure.sh</code>:</p>
 <pre><code>bash documentserver-configure.sh
 </code></pre>