diff --git a/Dockerfile b/Dockerfile
index 5003487..8c76f88 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -7,8 +7,12 @@
 RUN echo deb http://pkg.jenkins-ci.org/debian binary/ >> /etc/apt/sources.list
 RUN apt-get update && apt-get install -y jenkins
 RUN mkdir -p /var/jenkins_home && chown -R jenkins /var/jenkins_home
+ADD init.groovy /tmp/WEB-INF/init.groovy
+RUN apt-get install -y zip && cd /tmp && zip -g /usr/share/jenkins/jenkins.war WEB-INF/init.groovy
 USER jenkins
 
+
+
 # VOLUME /var/jenkins_home
 ENV JENKINS_HOME /var/jenkins_home
 EXPOSE 8080
diff --git a/init.groovy b/init.groovy
new file mode 100644
index 0000000..d13f089
--- /dev/null
+++ b/init.groovy
@@ -0,0 +1,5 @@
+import hudson.model.*;
+import jenkins.model.*;
+
+println "--> setting agent port for jnlp"
+Jenkins.instance.setSlaveAgentPort(50000)