diff --git a/Procfile b/Procfile
index 65a9880e6..e6944606a 100755
--- a/Procfile
+++ b/Procfile
@@ -1 +1 @@
-web: java $JAVA_OPTS -Dhttp.port=$PORT -classpath target/classes:lib/* net.yacy.yacy
\ No newline at end of file
+web: java $JAVA_OPTS -Dnet.yacy.server.localPort=$PORT -classpath target/classes:lib/* net.yacy.yacy
\ No newline at end of file
diff --git a/htroot/ConfigBasic.html b/htroot/ConfigBasic.html
index daef4777a..1d0c0df91 100644
--- a/htroot/ConfigBasic.html
+++ b/htroot/ConfigBasic.html
@@ -90,7 +90,7 @@
             <dl>
               <dt><label for="port">Peer Port: </label></dt>
               <dd>
-                <input type="text" name="port" id="port" value="#[defaultPort]#" size="5" maxlength="5" />&nbsp;&nbsp;&nbsp;
+				<input type="text" name="port" id="port" value="#[defaultPort]#" size="5" maxlength="5" #(hasSystemDefinedPort)#::disabled="disabled"#(/hasSystemDefinedPort)#/> #(hasSystemDefinedPort)#::(Set by system property '#[systemProperty]#')#(/hasSystemDefinedPort)#&nbsp;&nbsp;&nbsp;
                 <input type="checkbox" name="withssl" id="withssl" #(withsslenabled)#::checked="checked"#(/withsslenabled)#>with SSL (https enabled#(withsslenabled)#:: on port <a href="Settings_p.html?page=ProxyAccess">#[sslport]#</a>#(/withsslenabled)#)
               </dd>
               #(upnp)#::<dt>
diff --git a/htroot/ConfigBasic.java b/htroot/ConfigBasic.java
index 6144bd5af..155b23d6c 100644
--- a/htroot/ConfigBasic.java
+++ b/htroot/ConfigBasic.java
@@ -266,6 +266,8 @@ public class ConfigBasic {
 
         // set default values
         prop.putHTML("defaultName", sb.peers.mySeed().getName());
+        prop.put("hasSystemDefinedPort", env.getLocalPortSystemProperty() != null ? 1 : 0);
+        prop.put("hasSystemDefinedPort_systemProperty", serverSwitch.LOCAL_PORT_SYSTEM_PROPERTY);
         prop.put("defaultPort", env.getLocalPort());
         prop.put("withsslenabled", env.getConfigBool("server.https", false) ? 1 : 0);
         lang = env.getConfig("locale.language", "default"); // re-assign lang, may have changed
diff --git a/source/net/yacy/server/serverSwitch.java b/source/net/yacy/server/serverSwitch.java
index 0f3bbcbf0..fbcc982e5 100644
--- a/source/net/yacy/server/serverSwitch.java
+++ b/source/net/yacy/server/serverSwitch.java
@@ -58,6 +58,9 @@ import net.yacy.peers.Seed;
 import net.yacy.search.SwitchboardConstants;
 
 public class serverSwitch {
+	
+	/** Key of system property defining locally open http port */
+	public static final String LOCAL_PORT_SYSTEM_PROPERTY = "net.yacy.server.localPort";
 
 	// configuration management
 	private final File configFile;
@@ -217,26 +220,39 @@ public class serverSwitch {
 
 		return getConfigInt(key, dflt);
 	}
+	
+	/**
+	 * @return local http server port or null if system property is not defined
+	 */
+	public Integer getLocalPortSystemProperty() {
+		String systemDefinedPort = System.getProperty(LOCAL_PORT_SYSTEM_PROPERTY);
+		Integer localPort = null;
+		if(systemDefinedPort != null) {
+			try {
+				localPort = Integer.parseInt(systemDefinedPort);
+			} catch(NumberFormatException e) {
+				log.warn("System property " + LOCAL_PORT_SYSTEM_PROPERTY + " is not valid : it should be a integer.");
+			}
+		}
+		return localPort;
+	}
 
 	/**
 	 * Wrapper for {@link #getConfigInt(String, int)} to have a more consistent
 	 * API.
 	 * 
-	 * Default value 8090 will be used if no value is found
-         * 
-	 * @return the local port of this system
+	 * Default value 8090 will be used if no value is found in system properties and in configuration.
+     * 
+	 * @return the local http port of this system
 	 * @see #getPublicPort(String, int)
 	 */
 	public int getLocalPort() {
 
-		/* A system property "http.port" may override configuration 
+		/* A system property "net.yacy.server.localPort" may override configuration 
 		 * This is useful when running YaCy inside a container manager such as Heroku which decide which http port to use */
-		String systemDefinedPort = System.getProperty("http.port");
-		if(systemDefinedPort != null) {
-			try {
-				return Integer.parseInt(systemDefinedPort);
-			} catch(NumberFormatException e) {
-			}
+		Integer localPort = getLocalPortSystemProperty();
+		if(localPort != null) {
+			return localPort;
 		}
 		return getConfigInt("port", 8090);
 	}