Hello @Ganesh,
To run and configure multiple instances in a Single Tomcat Server do follow the steps:
First, you need to download Tomcat(I downloaded the Core .zip file.)
Now unzip the file and rename the folder “Tomcat.” You will get the below folder structure.
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Now suppose we want to run two instances on this single Tomcat.
Instance 1: edureka-one
Instance 2: edureka-two
First I want to create the edureka-one instance.
So make a copy of your downloaded Tomcat, and rename the folder “edureka-one,” and keep only “bin,” “conf,” “logs,” “temp,” “webapps,” and “work” files only.
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Now remove all the files from edureka-one/bin. In the “bin” folder of “app-one,” you can add a setenv.sh file to configure the JVM heap setting for that tomcat instance.
setenv.sh
export CATALINA_OPTS="$CATALINA_OPTS -Xms256m"
export CATALINA_OPTS="$CATALINA_OPTS -Xmx1024m"
export CATALINA_OPTS="$CATALINA_OPTS -XX:MaxPermSize=512m"
Now make another copy of the “edureka-one” folder and rename it “edureka-two.”
Now we have three folders in our directory
1) Tomcat
2) edureka-one
3) edureka-two
Now go to the “Tomcat” directory and delete the “conf,” “logs,” “temp,” “webapps,” and “work” folders. Create a new folder named “controller” inside Tomcat. In the “controller” folder, we will write a script to control all the Tomcat instances. Now, inside our Tomcat folder, we have:
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Now we will configure all the Tomcat instances (“edureka-one”, “edureka-two”) to different ports.
Configuration for edureka One
Go to this location, edureka-one/conf/, and open server.xml in edit mode. Suppose we want to run edureka-one in the “7050” port. Here is our configuration:
<?xml version='1.0' encoding='utf-8'?>
<Server port="7005" shutdown="SHUTDOWN">
<Listener className="org.apache.catalina.startup.VersionLoggerListener" />
<Listener className="org.apache.catalina.core.AprLifecycleListener" SSLEngine="on" />
<Listener className="org.apache.catalina.core.JasperListener" />
<Listener className="org.apache.catalina.core.JreMemoryLeakPreventionListener" />
<Listener className="org.apache.catalina.mbeans.GlobalResourcesLifecycleListener" />
<Listener className="org.apache.catalina.core.ThreadLocalLeakPreventionListener" />
<GlobalNamingResources>
<Resource name="UserDatabase" auth="Container"
type="org.apache.catalina.UserDatabase"
description="User database that can be updated and saved"
factory="org.apache.catalina.users.MemoryUserDatabaseFactory"
pathname="conf/tomcat-users.xml" />
</GlobalNamingResources>
<Service name="adminApp">
<Connector port="7050" protocol="HTTP/1.1"
connectionTimeout="20000"
redirectPort="7543" />
<Connector port="7509" protocol="AJP/1.3" redirectPort="7543" />
<Engine name="Catalina" defaultHost="localhost">
<Realm className="org.apache.catalina.realm.LockOutRealm">
<Realm className="org.apache.catalina.realm.UserDatabaseRealm"
resourceName="UserDatabase"/>
</Realm>
<Host name="localhost" appBase="webapps"
unpackWARs="true" autoDeploy="true">
<Valve className="org.apache.catalina.valves.AccessLogValve" directory="logs"
prefix="localhost_access_log." suffix=".txt"
pattern="%h %l %u %t "%r" %s %b" />
</Host>
</Engine>
</Service>
</Server>
Configuration of edureka Two
Go to this location, app-two/conf/, and open server.xml in edit mode. Suppose we want to run app-two in “7060” port. Here is our configuration:
<?xml version='1.0' encoding='utf-8'?>
<Server port="7006" shutdown="SHUTDOWN">
<Listener className="org.apache.catalina.startup.VersionLoggerListener" />
<Listener className="org.apache.catalina.core.AprLifecycleListener" SSLEngine="on" />
<Listener className="org.apache.catalina.core.JasperListener" />
<Listener className="org.apache.catalina.core.JreMemoryLeakPreventionListener" />
<Listener className="org.apache.catalina.mbeans.GlobalResourcesLifecycleListener" />
<Listener className="org.apache.catalina.core.ThreadLocalLeakPreventionListener" />
<GlobalNamingResources>
<Resource name="UserDatabase" auth="Container"
type="org.apache.catalina.UserDatabase"
description="User database that can be updated and saved"
factory="org.apache.catalina.users.MemoryUserDatabaseFactory"
pathname="conf/tomcat-users.xml" />
</GlobalNamingResources>
<Service name="adminApp">
<Connector port="7060" protocol="HTTP/1.1"
connectionTimeout="20000"
redirectPort="7643" />
<Connector port="7609" protocol="AJP/1.3" redirectPort="7643" />
<Engine name="Catalina" defaultHost="localhost">
<Realm className="org.apache.catalina.realm.LockOutRealm">
<Realm className="org.apache.catalina.realm.UserDatabaseRealm"
resourceName="UserDatabase"/>
</Realm>
<Host name="localhost" appBase="webapps"
unpackWARs="true" autoDeploy="true">
<Valve className="org.apache.catalina.valves.AccessLogValve" directory="logs"
prefix="localhost_access_log." suffix=".txt"
pattern="%h %l %u %t "%r" %s %b" />
</Host>
</Engine>
</Service>
</Server>
Note that any port number must not conflict with other port numbers.
Now we are going to write startup.sh and shutdown.sh inside the "tomcat/controller" location to start and stop each individual instance of tomcat.
startup.sh
#!/usr/bin/env sh
app_instance=$1;
BASE_TOMCAT=/location-to-tomcat-parent-directory
export CATALINA_HOME=$BASE_TOMCAT/tomcat
export CATALINA_BASE=$BASE_TOMCAT/$app_instance
$CATALINA_HOME/bin/startup.sh
shutdown.sh
#!/usr/bin/env sh
app_instance=$1;
BASE_TOMCAT=/location-to-tomcat-parent-directory/
export CATALINA_HOME=$BASE_TOMCAT/tomcat
export CATALINA_BASE=$BASE_TOMCAT/$app_instance
$CATALINA_HOME/bin/shutdown.sh
Everything is ready now. Copy paste your edureka-one.war file into “edureka-one/webapps” location and edureka-two.war file into “edureka-two/webapps” location and rename both files as ROOT.war .
Now you can start your apps using the following commands:
-
./startup.sh edureka-one
-
./startup.sh edureka-two
Our edureka-one URL, http://localhost:7050, and edureka-two URL, http://localhost:7060,
stop apps by using following commands:
This way, you can run more than one instance in a single Tomcat with different configurations on each instance.
Hope this work!!
Thank you!!!