[AWS EC2] How to use jconsole and visualVM [1] (remote connect Linux server)

Today, let's look at how to use jconsole and visualVm to monitor jvm memory on a Linux server.

recently, i met the java memory error so i studied java memory structure

and i found jconsole and visualVM which are tools that possible to monitor java memory utilization, available and capacity

jconsole and visualVm provide GUI-style memory informations

so if i could access remotely, it would be useful tool

 now let's start 

First of all, i'll tell you about my server and local environmental 

 

server

OS : Amazon linux2

WAS : tomcat7

java8

 

LOCAL

window, java

 

The way of setting to connect jconsole and visualVM are same, so i explain without distinction

 

[Download JMXRmote.jar in your Server ]

 

I'll download jmx remote.jar to my local and move it to my linux server

먼저, 로컬에서 톰캣 다운로드 페이지에 가서 자신의 버전에 맞는 jmx remote.jar 파일을 다운받아주세요.

 first of all, Download jmx remote.jar that matches your tomcat version from the site below 

tomcat.apache.org/download-70.cgi

 

Apache Tomcat® - Apache Tomcat 7 Software Downloads

Welcome to the Apache Tomcat® 7.x software download page. This page provides download links for obtaining the latest version of Tomcat 7.0.x software, as well as links to the archives of older releases. Unsure which version you need? Specification version

tomcat.apache.org

 

 

 and move it in [lib] folder that exists in your server's tomcat home directory

i put it directly through filezilla

i 

 

 

 

As above, you can see that  catalina-jmx-remote.jar is in lib folder of the tomcat home directory

You have to put it in the lib folder of your Tomcat home directory.

It may be different from my directory path

 

 

 

 

[Create setenv.sh file on your server]

 

서버의 톰캣 홈디렉토리의 bin폴더에서 setenv.sh를 작성하겠습니다. 

i will create setenv.sh in the [bin] folder in the servers' tomcat home directory

vi /usr/local/tomcat7/bin/setenv.sh

in my case, my tomcat home directory path is '/usr/local/tomcat7', so i setted like above

You will need to find and add your own Tomcat home directory path

 

and then add below code 

#!/bin/sh

JMX_OPTS=" -Dcom.sun.management.jmxremote -Dcom.sun.management.jmxremote.authenticate=false -Djava.rmi.server.hostname=your server ip -Dcom.sun.management.jmxremote.ssl=false"

CATALINA_OPTS=" ${JMX_OPTS} ${CATALINA_OPTS}" 

and write public ip of ec2 instance in the part marked   your server ip

 

 

 

 

Grant execution attribute 755 permission to setenv.sh file

 chmod 755 /usr/local/tomcat7/bin/setenv.sh

 

 

 

[Modify server.xml file in tomcat]

 

 Open the server.xml file which is in your tomcat home directory's conf folder through vi editor

 vi /usr/local/tomcat7/conf/server.xml

and add below <linstner>  tag

<Server port="8005" shutdown="SHUTDOWN">
  <Listener className="org.apache.catalina.mbeans.JmxRemoteLifecycleListener" rmiRegistryPortPlatform="9840" rmiServerPortPlatform="9841"/>

 

Not <server port="8005" .. > but add  only <Linstner ....   "9841" /> at the bottom of <server>

<server port="8005" shutdown=""SHUTDOWN"> is the original code  

 

[Edit security group in AWS Console]

 

Come back local, and edit security group in AWS Console

 

Click your security group used by your ec2 instance

 

 

보안그룹에 들어왔다면 인바운드 규칙 편집을 눌러주시고

If you entered security group page, click 'Edit inbound rules'

 As above, Open 9840 port and 9841 port

Ok now, the setting is ended

Restart tomcat 

and let's connect jconsole

 

Go to [bin] folder in local's java home directory and run the jconsole.exe

 

 

select 'Remot Process:' radio button

write down the 'public ip:9840' or 'public ip:9841'  and connect

 

 

Click Insecure connection button because we disabled ssl connection 

.

 

 

 yes, connection complete

 

you can see this image

 

Heap memory, thread and CPU usage are very convenient and userful information for managing java application

 

 

Next, let's connect VisualVM

 

 likewise, run the jvisualvm.exe in your bin folder of java home directory

 

 

 

 

 and then right-click on [Remote] icon and you can see add host. click it

 

 

 write down public ip on host name: box and remove default port

you can remove it with clicking 'Advanced Settings'

 and Click 'OK"

 

 

 if you followed me as tried

you can see new icon which name is public ip that we wrote

 

 

 right-click new icon and click 'Add JMX Connection'

 

 

 

write down 9840 or 9841 next to the public ip and don't check any checkbox

yes, also complete 

 

 

Finally, we finished remote connect to linux server with jconsole and visualVM 

 

however we did not set ID and password authentication

this way is very dangerous

the article is too long, so please  refer to the below link if you want