Hi I am currently facing a problem concerning the LD_LIBRARY_PATH variable in Websphere liberty. The application server is used within a docker container and the LD_LIBRARY_PATH variable is set within the server.env file. The first time, the container is starting, everything is fine. The ear is mounted into the container by directory and is getting started. The path within the Variable is resolved correctly.
While doing a rebuild of the ear, while the container is still running (for a shorter development turnaround) the application server detects the changes and restarts the new ear. But at his point, the LD_LIBRARY_PATH cannot be resolved anymore without any change in the server.env file.
Did anybody face the same problem yet and found a solution to it ?
If you need more information feel free to ask.
Related
In our Linux environment applications are restarted periodically (the reasons aren't important here). It would be convenient for us to deploy new versions of an application by copying the application Spring Boot jar on top of the existing (old) jar thereby overwriting it and then simply wait for the application to restart (that is, the JVM running the application to restart).
However, this seems to not work. We get different kinds of errors - sometimes the app just hangs, sometimes we get a ClassNotFoundException. It's as if Spring Boot (or something inside Spring Boot) reopens the jar and expects it to be the same one it was when the application was originally started.
We had a look through Spring's common application properties, but didn't see anything appropriate. Is there a way to make this work? When we were using WAR files we configured the servlet container to unpack the WAR file and run from the unpacked version. Can we do something similar with Spring Boot?
First of all the errors you are experiencing can come from multiple sources. Usually replacing the file from a process is not a big problem as the whole file is loaded into memory before execution. Java is a little bit different, because the actual process that is running is the JVM and it only loads the jar file from disk. The JVM loads classes only on demand, this means if there was any class that was not loaded before it will try to load it and most likely fail, if the jar file is different. In the case of spring boot there are also other resources (such as HTML files) inside the jar file that are dynamically loaded.
You mentioned you are using a linux environment. If you can just replace your startup with a script you can just copy the jar and start it from the copied location:
#!/bin/bash
JAR_NAME="spring-boot.jar"
NEW_JAR_NAME=".$JAR_NAME" # Use an appropriate name here
cp $JAR_NAME $NEW_JAR_NAME
java -jar $NEW_JAR_NAME
rm $NEW_JAR_NAME
Now every time you start the application a copy is being made and started from there. You can replace the original jar and on the next restart the new application will load.
You coud also use rsync instead of cp to avoid copying the same jar twice, if the application is restarted multiple times without changing the jar.
It would be convenient for us to deploy new versions of an application
by copying the Spring Boot jar on top of the existing (old) jar and
then simply wait for the application to restart
Why would you do such a thing to yourself? You are trying solve a usecase that's against best practices, sound like asking for trouble just to avoid an app restart. When you are doing a deployment, you need to make sure the deployment went through, otherwise how will you troubleshoot if something goes wrong in your application, you will have one more variable in hand when you troubleshoot, i,e the uncertainty of current version of the code.
If you are having downtime while deploying (I am assuming thats why you want to limit the restarts), why don't you bring up another instance with the newer version of code and once its healthy shutdown the old one
We have a config folder structure in apps like this:
config
config.author.test
config.author.stage
These have config.runmode.env values
I wanted to know from where It picks the "env" value.
I thought it is coming from runmodes. but in the instances, stage or test is nowhere.
Can anyone please help me know where does the AEM configs picks the value or where do we define those env value. Is it in some OSGi configuration or from where.
If you are not using the AEM runtime for the AEM Cloud SDK, then the run modes can be set in other ways as well apart from the sling.properties file. So depending on how you are starting your AEM server check if the run modes have been specified using the other options.
If you are using the AEM runtime from the cloud SDK, then check if the Jar file is named as shown in the Quickstart jar startup modes.
I have a tomcat server with several applications. Then, I gonna deploy spring boot application on tomcat. But before deploy I set an environment variable in my server. Because of This application should use the environment variable. So I wish not to restart my tomcat after set new environment variable in my server.
Have you any solution? Help me, please?
You cannot change environment variables from Java without resorting to dirty tricks.
You can, however, change the values of system properties. Consider using system properties instead of environment variables to adjust the behavior of your application.
Better yet, don't use globally-visible/mutatable configuration and instead configure components individually through some other mechanism, such as a configuration file.
Hi I want my spring boot web project to be deployed both on development and production environment and it should be run on specific profile based setting.
I googled on how to do that, and first of all that I have searched is defining application-{profile name}.properties properly in the src/main/resources classpath.
Now the problem is how to set profiles.
Since I am working on tomcat 8 in linux, there should be some configuration but I don't know how to do that.
and I am also curious that when my project is packaged as war file, java -jar {filename} -Dspring.active.profile=blahblah will not be work, but I think there is an alternative way.
plus, is there an way to set profile on tomcat 8 in Windows 10 ?
Thanks you
First:
I will recommend get rid of dedicated tomcat server and use embedded tomcat, jetty etc. Build your web apps as jar files and just run them. (of course if you don't have any limitations)
Second: You can do this either system property or env variable.
If you go with system property (order is important)
java -Dspring.profiles.active=blahblah -jar {filename}
If you go with env variable you need specify
SPRING_PROFILES_ACTIVE=blahblah
I'm creating a web application that needs to run on Weblogic 12c. The application is set-up to have an external XML config file, that is provided by the user, read using the Spring ClasspathResource bean (i.e. <bean id="myResource" value="config.xml>). On a linux environment, this works fine when the file is placed in the DOMAIN_HOME. However, when I attempt the same on a Windows environment, I get a FileNotFoundException as soon as I attempt to access the Resource instance.
The WebLogic installations are from the same jar executable installer and are absolutely identical, so I can't seem to figure out why this doesn't work on Windows. I'd appreciate ANY help whatsoever...
Just to clarify, I know I can get around this on Windows by informing the user to set a CLASSPATH environment variable but I'd rather not.