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Want to change the context path in Spring boot application in an external Tomact server version 9

I want to deploy a Spring boot application in an external Tomcat server version 9. I am able to deploy it and working the endpoints also. But properties I have set in application.properties file those are not working. Like server.servlet.context-path=/myapp is is not working instead the context path which I am getting is http://localhost:8080/myapp-0.0.1-SNAPSHOT/api/ping.
I am using 2.3.10.RELEASE and Java 1.8 and Tomcat version 9.0.46 Can anyone please help me out with this.
But everything is perfectly working on embedded tomcat. Thanks in advance and any suggestion, comment is highly appreciated.
Can anyone please help me with how I can do this - My war file name would be myapp-0.1.war but the context path of the application would be like this localhost:8080/myapp/api/ping

Use finalName property in your build file (pom.xml for maven)
<finalName>myapp</finalName>

When you run a Spring Boot application in an external servlet container, the server.* properties do not apply.
If you are willing to change the naming convention you can drop a WAR file named myapp##0.1.war in the $CATALINA_BASE/webapps directory and benefit from parallel deployment (cf. parallel deployment).
If you want to stick to your naming convention, you can create a folder for your WAR files (e.g. $CATALINA_BASE/webapps-available) and create a deployment descriptor $CATALINA_BASE/conf/<engine_name>/<host_name>/<context_path>.xml (in your case probably $CATALINA_BASE/conf/Catalina/localhost/myapp.xml) with the following content:
<Context docBase="${catalina.base}/webapps-available/myapp-0.1.war" />

websphere liberty - Not able to generate application specific logging using slf4j or log4j

How can I generate Application specific logs in IBM Websphare Liberty server, I am using SLF4j, the message.log and console.log is updating fine but the application specific logs are not getting generated.
If the logging issue can be resolved using Log4j, then also will work for me.
Tried loading log4j2 file explicitly in static block and also placed in resource folder, both didnt worked.
able to see liberty server log but application logs are not generating at all.

The root cause of not seeing log4j logs is usually because the log4j2 configuration file is not being picked up by the classloader. You have a few options here to solve your problem.
Copy to Liberty shared-library directory. It can be one of the following:
${shared.config.dir}/lib/global
${server.config.dir}/lib/global
You can refer to IBM websites to find out the exact location of ${shared.config.dir} and ${server.config.dir} in your Liberty installation
at here
Alternatively, you can place the log4j configuration file anywhere on your file system and add the following lines to your server.xml
<library id="log4jConfig">
<folder dir="/{directory containning log4j config file}" scanInterval="5s" />
</library>
<webApplication id="myapp" location="myapp.war" name="My App"/>
<classloader commonLibraryRef="log4jConfig"/>
</webApplication>
Set as a JVM argument inside the jvm.options file
-Dlog4j.configurationFile=file:/path/to/log4j2.xml
Package it inside your maven application war file under src/main/resources

Blow fix worked for me, from the application class or entry point use below code to reload the slf4j configuration.
private static final org.slf4j.Logger LOGGER = org.slf4j.LoggerFactory.getLogger(theClassfromwheregeneratinglogs.class);
static {
try {
LoggerContext context = (LoggerContext) LoggerFactory.getILoggerFactory();
JoranConfigurator configurator = new JoranConfigurator();
configurator.setContext(context);
// Call context.reset() to clear any previous configuration, e.g. default
// configuration. For multi-step configuration, omit calling context.reset().
context.reset();
configurator.doConfigure("/appserver/wlpusr/servers/applogs/logback.xml"); //This will reload the slf4j configuration from the given file location.
} catch (JoranException je) {
// StatusPrinter will handle this
}}

How do I change log level in runtime without restarting Vert.x application

I know that we can change log level by putting it in vertx-default-jul-logging.properties file.
java.util.logging.ConsoleHandler.formatter=java.util.logging.SimpleFormatter
java.util.logging.ConsoleHandler.level=FINER
java.util.logging.FileHandler.limit=10000000
java.util.logging.FileHandler.count=10
java.util.logging.FileHandler.level=FINER
java.util.logging.FileHandler.formatter=java.util.logging.SimpleFormatter
But I need to restart the application when we change log level in this file as it gets built with application. Is there any way to change the log level without restarting the application like we can do in jboss by jboss cli.

This file doesn't have to be built with the application. It just has to be on the classpath.
But anyway, I don't believe JDK logging supports hot reload of a configuration file. There are other logging tools which do though. Like Logback-classic.
Logback-classic can scan for changes in its configuration file and automatically reconfigure itself when the configuration file changes.
For example, to reload every five seconds:
<configuration scan="true" scanPeriod="5 seconds" >
...
</configuration>
Vert.x can be configured to use different logging frameworks. To do so, you must set the vertx.logger-delegate-factory-class-name system property. As Logback-classic is an slf4j implementation, you need:
-Dvertx.logger-delegate-factory-class-name=io.vertx.core.logging.SLF4JLogDelegateFactory

Does depedent project in java take log4j config of parent project?

I am having project A and project B, A has jar dependency of project B. I have defined log4j.xml in project A but I am not able to see logs of sub-project(B.jar) in file appender as well as tomcat server console. Does project B will take log4j.xml form parent project A or not then which config does it use?

There is one log4j config for your entire JVM (unless you're working in a containerized environment using class loaders and.... that's not what's described).
Missing log messages implies that the configuration from log4j either (a) isn't what you think it is (i.e. a different log4j.xml is being used) or (b) doesn't have the right settings for the missing log lines.
Adding the following to the JVM at startup may help:
-Dlog4j.debug
It may also be possible to browse the log4j settings via MBeans in jconsole.

If you want all apps (WAR files) in a Tomcat instance to have the same logging configs, the simple solution is to arrange that all WAR files have a copy of the same config file.
If you want the apps to share a common logging framework (with a single configuration), then you should consider using Context Selectors, as described in the Log4j 2 documentation.
Using Context Selectors
There are a few patterns for achieving the desired state of logging separation using ContextSelectors:
Place the logging jars in the container's classpath and set the system property log4j2.contextSelector to org.apache.logging.log4j.core.selector.BasicContextSelector. This will create a single LoggerContext using a single configuration that will be shared across all applications.
Place the logging jars in the container's classpath and use the default ClassLoaderContextSelector. Follow the instructions to initialize Log4j 2 in a web application. Each application can be configured to share the same configuration used at the container or can be individually configured. If status logging is set to debug in the configuration there will be output from when logging is initialized in the container and then again in each web application.
Follow the instructions to initialize Log4j 2 in a web application and set the system property or servlet context parameter log4j2.contextSelector to org.apache.logging.log4j.core.selector.JndiContextSelector. This will cause the container to use JNDI to locate each web application's LoggerContext. Be sure to set the isLog4jContextSelectorNamed context parameter to true and also set the log4jContextName and log4jConfiguration context parameters.
The exact method for setting system properties depends on the container. For Tomcat, edit $CATALINA_HOME/conf/catalina.properties. Consult the documentation for other web containers.
I don't think there is a direct equivalent in Log4j 1.x.

How to deploy the same webapp with different logging? (Tomcat, Solr)

We are using multiple solr instances on tomcat but want that they log into different log files. How could we do this?
We are using the follwing xml file under tomcat/conf/Catalina/localhost to make it working:
<Context docBase="/pathtosolr/dist/apache-solr-1.4.0.war" debug="0" crossContext="true" >
<Environment name="solr/home" type="java.lang.String" value="/pathtosolr/solr" override="true" />
</Context>
Update: From Jems answer I found this documentation:
Tomcat offers a choice between settings for all applications or settings specifically for the Solr application.
To change logging settings for Solr only, edit tomcat/webapps/solr/WEB-INF/classes/logging.properties. You will need to create the classes directory and the logging.properties file. You can set levels from FINEST to SEVERE for a class or an entire package. Here are a couple of examples:
org.apache.commons.digester.Digester.level = FINEST
org.apache.solr.level = WARNING
Alternately, if you wish to change Tomcat’s JDK Logging API settings for every application in this instance of Tomcat, edit tomcat/conf/logging.properties.
See the documentation for the SLF4J Logging API for more information:
http://slf4j.org/docs.html

You might wanna take a look at this page: http://globalgateway.wordpress.com/2010/01/06/configuring-solr-1-4-logging-with-log4j-in-tomcat/

There seems to be no good solution:
2008 and 2010
except repacking the solr.war file with a different logging configuration file.
Update: see accepted answer!