diff --git a/content/rancher/v2.x/en/installation/requirements/_index.md b/content/rancher/v2.x/en/installation/requirements/_index.md
index 9797f8eb35e..9d74fc55c4e 100644
--- a/content/rancher/v2.x/en/installation/requirements/_index.md
+++ b/content/rancher/v2.x/en/installation/requirements/_index.md
@@ -17,6 +17,7 @@ Rancher is tested on the following operating systems and their subsequent non-ma
 - Docker 18.06.x, 18.09.x
 - Red Hat Enterprise Linux (RHEL)/CentOS 7.6 (64-bit x86)
 - RHEL Docker 1.13
+- Oracle Linux 7 update 6* (64-bit x86)
 - Docker 17.03.x, 18.06.x, 18.09.x
 - RancherOS 1.5.1 (64-bit x86)
 - Docker 17.03.x, 18.06.x, 18.09.x
@@ -24,9 +25,11 @@ Rancher is tested on the following operating systems and their subsequent non-ma
   - Requires Docker Engine - Enterprise Edition (EE)
   - Nodes with Windows Server core version 1809 should use Docker EE-basic 18.09
   - Nodes with Windows Server core version 1903 should use Docker EE-basic 19.03
-- Supported for worker nodes only. See [Configuring Custom Clusters for Windows]({{< baseurl >}}/rancher/v2.x/en/cluster-provisioning/rke-clusters/windows-clusters/)
+  - Supported for worker nodes only. See [Configuring Custom Clusters for Windows]({{< baseurl >}}/rancher/v2.x/en/cluster-provisioning/rke-clusters/windows-clusters/)
 
-If you are using RancherOS, make sure you switch the Docker engine to a supported version using:<br>
+\* The standard Oracle Linux image in the AWS Cloud Market (OL7.6-x86_64-HVM-2019-01-29) has default firewall rules that block communication with Helm. You must open the ports according to the [port requirements]({{<baseurl>}}/rancher/v2.x/en/installation/references) before doing a high-availability installation of Rancher with Helm.
+
+If you are using RancherOS, make sure you switch the Docker engine to a supported version using:
 
 ```
 # Look up available versions