Put back port 8444 warning pending discussion

Author: matyasselmeci

docs/data/osdf/install-cache-rpm.md

@@ -19,7 +19,8 @@ Before starting the installation process, consider the following requirements:
 * __Host certificate:__ Required for authentication.  See note below.
 * __Network ports:__ The cache service requires the following ports open:
   * Inbound TCP port 8443 for file access via the HTTP(S) and XRoot protocols.
-  * Inbound TCP port 8444 for access to the web interface for monitoring and configuration.
+  * (Optional) Inbound TCP port 8444 for access to the web interface for monitoring and configuration;
+    if enabled, access to this port should be restricted to the LAN.
 * __Service requirements:__
     * A cache serving the OSDF federation as a regional cache should have at least:
         * 8 cores