I have configured custom server.xml with the reference taken from downloaded tomcat distribution and have updated port number and others, when I had issues followed below answer.
embedded tomcat custom server.xml configuration issues
Note:It is working only in tomcat7-maven-plugin artifact with version 2.1 but not 2.2
Find my pom.xml and server.xml
<project>
...
<packaging>war or pom</packaging>
...
<build>
...
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<configuration>
<source>${java-version}</source>
<target>${java-version}</target>
</configuration>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-war-plugin</artifactId>
<configuration>
<warName>secured-sample-webapp</warName>
<webResources>
<resource>
<directory>src/main/webapp</directory>
<filtering>true</filtering>
<includes>
<include>**/*.tag</include>
<include>**/*.jsp</include>
</includes>
</resource>
<resource>
<directory>src/main/webapp</directory>
<filtering>false</filtering>
<excludes>
<exclude>**/*.tag</exclude>
<exclude>**/*.jsp</exclude>
</excludes>
</resource>
</webResources>
<packagingExcludes>less/**</packagingExcludes>
</configuration>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-dependency-plugin</artifactId>
<executions>
<execution>
<id>install</id>
<phase>install</phase>
<goals>
<goal>sources</goal>
</goals>
</execution>
</executions>
</plugin>
<plugin>
<groupId>org.apache.tomcat.maven</groupId>
<artifactId>tomcat7-maven-plugin</artifactId>
<version>2.1</version>
<executions>
<execution>
<id>tomcat-run</id>
<goals>
<goal>exec-war-only</goal>
</goals>
<phase>package</phase>
<configuration>
<path>/secured-sample-webapp</path>
<warDirectory>target/secured-sample-webapp</warDirectory>
<!-- optional, needed only if you want to use a preconfigured server.xml file -->
<serverXml>src/main/tomcatconf/server.xml</serverXml>
<!-- optional values which can be configurable -->
<attachArtifactClassifier>exec-war</attachArtifactClassifier>
<attachArtifactClassifierType>jar</attachArtifactClassifierType>
<finalName>secured-sample-webapp-exec.jar</finalName>
<enableNaming>true</enableNaming>
</configuration>
</execution>
</executions>
</plugin>
...
</plugins>
...
</build>
...
</project>
and
Server.xml
<Server port="8005" shutdown="SHUTDOWN">
<!-- <Listener className="org.apache.catalina.startup.VersionLoggerListener" /> -->
<!-- Security listener. Documentation at /docs/config/listeners.html
<Listener className="org.apache.catalina.security.SecurityListener" />
-->
...
<Service>
...
<Engine>
...
<Host name="localhost" appBase="webapps"
unpackWARs="true" autoDeploy="true">
<Context docBase="../../secured-sample-webapp" path="/secured-sample-webapp" reloadable="true" />
<!-- SingleSignOn valve, share authentication between web applications
Documentation at: /docs/config/valve.html -->
<!--
<Valve className="org.apache.catalina.authenticator.SingleSignOn" />
-->
<!-- Access log processes all example.
Documentation at: /docs/config/valve.html
Note: The pattern used is equivalent to using pattern="common" -->
<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>