The timezone rules within Java compute nodes are delivered by means of the dedicated TZdata package, comprised in each appropriate container. Follow the instructions below in case you need to update it to the latest version or to change the timezone your server is working at.
Despite the fact the newest TZdata package edition is integrated to a node during its creation, after some time it becomes outdated due to periodical changing of the intrinsic data. Thus, old containers may require the corresponding updating from time to time (particularly, in order not to be recreated each time this is needed). For that, a special embedded TZUpdater tool is used, intended for keeping your timezone data accurate and up-to-date. It is a fairly simple to use and can be run with a single-line command, you just need to:
1. Connect to your Java environment via SSH and select the corresponding container:
Tip: In the case you haven’t performed similar operations before, you need to:
2. Once inside, you can check the currently used TZdata version by executing the following string:
java -jar /usr/java/utils/tzupdater.jar -V
3. If you’ve observed the corresponding package in the chosen container is outdated, you can update the timezone information using the embedded TZUpdater tool:
java -jar /usr/java/utils/tzupdater.jar -u
As you can see, getting the latest timezone package version for Java is a really simple operation with Jelastic.
Now, let’s discover how to check and change the application server’s local time - we’ll consider this on the example of a Tomcat 7 server.
1. Let’s set the current timestamp to be output at the server’s start page for evident displaying of the upcoming configuration changes - just paste the code below instead of the webapps/ROOT/index.jsp file’s default content (use the inbuilt Jelastic Configuration Manager for that).
2. Save the changes and Open your environment in browser with the corresponding button to see current server time, like:
3. In order to change the actual timezone, perform the following:
Switch to the variables.conf configuration file and add the -Duser.timezone variable with the required zone as a value (find the complete list here), for example:
Note: Depending on a particular application server used, the location of this file may vary:
- Tomcat, Tomee - /opt/tomcat/conf/variables.conf
- Tomcat8 - /opt/shared/conf/variables.conf
- Jetty 6 - /opt/jetty/etc/variables.conf
- Jetty 8/9 - /opt/shared/conf/etc/variables.conf
Access the GF admin panel, go to the Configurations > gfcluster-config (or server-config for GF 4) > JVM Settings > JVM Options section and click the Add JVM Option button. Paste the corresponding string within the appeared input field:
Navigate to the /opt/shared/bin/standalone.conf file and add the abovementioned variable to the Java VM options section (approximately at the 75th string, right before the closing quotation mark):
Switch to the /opt/shared/bin/standalone.conf configuration file and declare the corresponding variable using the following format:
4. Save the made adjustment and Restart your application server in order to apply the new settings. Now, just refresh the server start page or click Open in browser again to see the updated local time:
Great, new rules were applied successfully. In such a way, you can set any desired time location for your server without any problems, in a matter of a minutes.