diff --git a/en_US/installation/0-install.iredmail.on.rhel.md b/en_US/installation/0-install.iredmail.on.rhel.md
index 10b50e36..ab3670f8 100644
--- a/en_US/installation/0-install.iredmail.on.rhel.md
+++ b/en_US/installation/0-install.iredmail.on.rhel.md
@@ -55,7 +55,7 @@ $ hostname -f
 mx.example.com
 ```
 
-On RHEL/CentOS/Scientific Linux, hostname is set in two files:
+On RHEL/CentOS Linux, hostname is set in two files:
 
 1. `/etc/hostname`:
 
@@ -102,14 +102,22 @@ Disable it immediately without rebooting your server.
 ### Enable yum repositories for installing new packages
 
 * On CentOS:
-    - Enable official yum repositories. On CentOS 8, please make sure repo
-      `AppStream` and `PowerTools` are enabled.
+    - Enable official yum repositories. On CentOS 8 and CentOS 8 Stream, please
+      make sure repo `appstream` and `powertools` are enabled.
     - Enable repo `epel`.
     - __DISABLE__ all other third-party yum repositories to avoid package conflict.
 
 * On Red Hat Enterprise Linux:
-    - Enable Red Hat Network to install packages, or create a local yum repository with DVD/CD ISO images.
+    - Enable Red Hat Network to install packages, or create a local yum
+      repository with DVD/CD ISO images.
     - Enable `epel` repo (you can enable it by installing package `epel-release`)
+    - On Red Hat Enterprise Linux, please enable repository `codeready-builder-for-rhel-8-x86_64-rpms`
+      and `epel` with commands below:
+
+```
+dnf -y install https://dl.fedoraproject.org/pub/epel/epel-release-latest-8.noarch.rpm
+subscription-manager repos --enable codeready-builder-for-rhel-8-x86_64-rpms
+```
 
 !!! attention
 
diff --git a/html/install.iredmail.on.rhel.html b/html/install.iredmail.on.rhel.html
index aacd56da..5cfca689 100644
--- a/html/install.iredmail.on.rhel.html
+++ b/html/install.iredmail.on.rhel.html
@@ -91,7 +91,7 @@ recommended to set a fully qualified domain name (FQDN) hostname.</p>
 mx.example.com
 </code></pre>
 
-<p>On RHEL/CentOS/Scientific Linux, hostname is set in two files:</p>
+<p>On RHEL/CentOS Linux, hostname is set in two files:</p>
 <ol>
 <li>
 <p><code>/etc/hostname</code>:</p>
@@ -128,8 +128,8 @@ set below value instead:</p>
 <li>
 <p>On CentOS:</p>
 <ul>
-<li>Enable official yum repositories. On CentOS 8, please make sure repo
-  <code>AppStream</code> and <code>PowerTools</code> are enabled.</li>
+<li>Enable official yum repositories. On CentOS 8 and CentOS 8 Stream, please
+  make sure repo <code>appstream</code> and <code>powertools</code> are enabled.</li>
 <li>Enable repo <code>epel</code>.</li>
 <li><strong>DISABLE</strong> all other third-party yum repositories to avoid package conflict.</li>
 </ul>
@@ -137,11 +137,18 @@ set below value instead:</p>
 <li>
 <p>On Red Hat Enterprise Linux:</p>
 <ul>
-<li>Enable Red Hat Network to install packages, or create a local yum repository with DVD/CD ISO images.</li>
+<li>Enable Red Hat Network to install packages, or create a local yum
+  repository with DVD/CD ISO images.</li>
 <li>Enable <code>epel</code> repo (you can enable it by installing package <code>epel-release</code>)</li>
+<li>On Red Hat Enterprise Linux, please enable repository <code>codeready-builder-for-rhel-8-x86_64-rpms</code>
+  and <code>epel</code> with commands below:</li>
 </ul>
 </li>
 </ul>
+<pre><code>dnf -y install https://dl.fedoraproject.org/pub/epel/epel-release-latest-8.noarch.rpm
+subscription-manager repos --enable codeready-builder-for-rhel-8-x86_64-rpms
+</code></pre>
+
 <div class="admonition attention">
 <p class="admonition-title">Attention</p>
 <p>Since official RHEL/CentOS and EPEL repositories don't have all