OSDOCS-934: Add a note

Author: xenolinux

modules/nw-egressnetworkpolicy-about.adoc

@@ -30,6 +30,11 @@ to internal hosts that are outside the {product-title} cluster.
 
 For example, you can allow one project access to a specified IP range but deny the same access to a different project. Or you can restrict application developers from updating from Python pip mirrors, and force updates to come only from approved sources.
 
+[NOTE]
+====
+Egress firewall does not apply to the host network namespace. Pods with host networking enabled are unaffected by egress firewall rules.
+====
+
 You configure an egress firewall policy by creating an {kind} custom resource (CR) object. The egress firewall matches network traffic that meets any of the following criteria:
 
 - An IP address range in CIDR format