Tomcat installation on linux

1. Install java on linux *
2. we have Java v1.8.x

### Install Apache Tomcat
Download tomcat packages from https://tomcat.apache.org/download-80.cgi onto /opt on linux instance
```sh
# create tomcat directory
cd /opt
wget http://mirrors.fibergrid.in/apache/tomcat/tomcat-8/v8.5.35/bin/apache-tomcat-8.5.35.tar.gz
tar -xvzf /opt/apache-tomcat-8.5.35.tar.gz
```
give executing permissions to startup.sh and shutdown.sh which are under bin.
```sh
chmod +x /opt/apache-tomcat-8.5.35/bin/startup.sh shutdown.sh
```
check the $PATH
and then select the path and create the link
create link files for tomcat startup.sh and shutdown.sh
```sh
ln -s /opt/apache-tomcat-8.5.35/bin/startup.sh /usr/local/bin/tomcatup
ln -s /opt/apache-tomcat-8.5.35/bin/shutdown.sh /usr/local/bin/tomcatdown
tomcatup
```
#### check point :
access tomcat application from browser on prot 8080
http://<Public_IP>:8080

Using unique ports for each application is a best practice in an environment. But tomcat and Jenkins runs on ports number 8080. Hence lets change tomcat port number to 8090. Change port number in conf/server.xml file under tomcat home
```sh
cd /opt/apache-tomcat-8.5.35/conf
# update port number in the “connecter port” field in server.xml
# restart tomcat after configuration update
tomcatdown
tomcatup
```
#### check point :
access tomcat application from browser on prot 8090
http://<Public_IP>:8090

now application is accessible on port 8090. but tomcat application doesnt allow to login from browser. changing a default parameter in context.xml does address this issue
```sh
#search for context.xml
find / -name context.xml
```
above command gives 3 context.xml files. comment (<! — & →) `Value ClassName` field on files which are under webapp directory.
After that restart tomcat services to effect these changes
```sh
tomcatdown
tomcatup
```
Update users information in the tomcat-users.xml file
goto tomcat home directory and Add below users to conf/tomcat-user.xml file
```sh
<role rolename=”manager-gui”/>
<role rolename=”manager-script”/>
<role rolename=”manager-jmx”/>
<role rolename=”manager-status”/>
<user username=”admin” password=”admin” roles=”manager-gui, manager-script, manager-jmx, manager-status”/>
<user username=”deployer” password=”deployer” roles=”manager-script”/>
<user username=”tomcat” password=”s3cret” roles=”manager-gui”/>
```
Restart serivce and try to login to tomcat application from the browser. This time it should be Successful

Check the version Tomcat : Navigate the tomcat-folder execute the below command
java -cp lib/catalina.jar org.apache.catalina.util.ServerInfo