release plugin issue

pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
  <modelVersion>4.0.0</modelVersion>

  <parent>
    <groupId>org.jenkins-ci.plugins</groupId>
    <artifactId>plugin</artifactId>
    <!-- Baseline Jenkins version you use to build and test the plugin. Users must have this version or newer to run. -->
    <version>2.11</version>
    <relativePath/>
  </parent>
  
   <properties>
    <jenkins.version>1.609.1</jenkins.version>
    <hpi-plugin.version>1.106</hpi-plugin.version>
      <java.level>8</java.level>
  </properties>
  
  <artifactId>sinatra-chef-builder</artifactId>
  <version>1.5-SNAPSHOT</version>
  <packaging>hpi</packaging>

  <name>Chef Sinatra Jenkins plugin</name>
  <description>Chef Sinatra Jenkins plugin</description>
  <url>https://wiki.jenkins-ci.org/display/JENKINS/Chef+Sinatra+Jenkins+Plugin</url>
  <licenses>
    <license>
      <name>MIT License</name>
      <url>http://opensource.org/licenses/MIT</url>
    </license>
  </licenses>
  
   <scm>
      <connection>scm:git:git://github.com/jenkinsci/chefbuilder-plugin.git</connection>
      <!--<developerConnection>scm:git:git@github.com:jenkinsci/chefbuilder-plugin.git</developerConnection> -->
       <developerConnection>scm:git:ssh://git@github.com/jenkinsci/chefbuilder-plugin.git</developerConnection>
      <url>http://github.com/jenkinsci/chefbuilder-plugin</url>
    <tag>HEAD</tag>
  </scm>
  
   <developers>
      <developer>
        <id>irfanjs</id>
        <name>Irfan Sayed</name>
        <email>irfu.sayed@gmail.com</email>
      </developer>
  </developers>

 
  <repositories>
    <repository>
      <id>repo.jenkins-ci.org</id>
      <url>http://repo.jenkins-ci.org/public/</url>
    </repository>
  </repositories>
  <pluginRepositories>
    <pluginRepository>
      <id>repo.jenkins-ci.org</id>
      <url>http://repo.jenkins-ci.org/public/</url>
    </pluginRepository>
  </pluginRepositories>
   <dependencies>
 
<dependency>
<groupId>com.jcraft</groupId>
<artifactId>jsch</artifactId>
<version>0.1.53</version>
</dependency>

<dependency>
<groupId>org.mortbay.jetty</groupId>
<artifactId>jsp-2.1</artifactId>
<version>6.1.14</version>
</dependency>

</dependencies>

</project>

settings.xml

<settings>
  <pluginGroups>
    <pluginGroup>org.jenkins-ci.tools</pluginGroup>
  </pluginGroups>

  <profiles>
    <!-- Give access to Jenkins plugins -->
    <profile>
      <id>jenkins</id>
      <activation>
        <activeByDefault>true</activeByDefault> <!-- change this to false, if you don't like to have it on per default -->
      </activation>
      <repositories>
        <repository>
          <id>repo.jenkins-ci.org</id>
          <url>https://repo.jenkins-ci.org/public/</url>
        </repository>
      </repositories>
      <pluginRepositories>
        <pluginRepository>
          <id>repo.jenkins-ci.org</id>
          <url>https://repo.jenkins-ci.org/public/</url>
        </pluginRepository>
      </pluginRepositories>
    </profile>
  </profiles>
  <mirrors>
    <mirror>
      <id>repo.jenkins-ci.org</id>
      <url>https://repo.jenkins-ci.org/public/</url>
      <mirrorOf>m.g.o-public</mirrorOf>
    </mirror>
  </mirrors>
</settings>

what i did.doc

I have downloaded the current version of my plugin from URL:https://github.com/jenkinsci/sinatra-chef-builder-plugin
the current version was 1.3
made the changes in the code
build and compilation works fine. tested the plugin in local environment and it works fine.
now the current version in POM is : 1.4-SNAPSHOT as it is a development version 
now, i treid releasing plugin
I published my new public key in github
now, pushed all the new changes in the code to github using following command
  git add pom.xml src
  git commit -m "new version"
  git push origin master 
then using maven command, tried to release the plugin
  mvn release:prepare release:perform 
it asks me few questions like : which is next development version and what is the new release version wou;ld be :
i accepeted all the default option and proceed
then got the following error :

       [INFO] Copy webapp webResources to C:\sinatra-chef-builder-plugin\target\checkout\target\sinatra-chef-builder
    [INFO] Assembling webapp sinatra-chef-builder in C:\sinatra-chef-builder-plugin\target\checkout\target\sinatra-chef-builder
    [INFO] Generating hpi C:\sinatra-chef-builder-plugin\target\checkout\target\sinatra-chef-builder.hpi
    [INFO] Building jar: C:\sinatra-chef-builder-plugin\target\checkout\target\sinatra-chef-builder.hpi
    [INFO]
    [INFO] --- maven-install-plugin:2.3.1:install (default-install) @ sinatra-chef-builder ---
    [INFO] Installing C:\sinatra-chef-builder-plugin\target\checkout\target\sinatra-chef-builder.hpi to C:\Users\irfanjs\.m2\repository\org\jenkins-ci\plugins\sinatra-chef-builder\1.4\sinatra-chef-builder-1.4.hpi
    [INFO] Installing C:\sinatra-chef-builder-plugin\target\checkout\pom.xml to C:\Users\irfanjs\.m2\repository\org\jenkins-ci\plugins\sinatra-chef-builder\1.4\sinatra-chef-builder-1.4.pom
    [INFO] Installing C:\sinatra-chef-builder-plugin\target\checkout\target\sinatra-chef-builder.jar to C:\Users\irfanjs\.m2\repository\org\jenkins-ci\plugins\sinatra-chef-builder\1.4\sinatra-chef-builder-1.4.jar
    [INFO]
    [INFO] --- maven-deploy-plugin:2.6:deploy (default-deploy) @ sinatra-chef-builder ---
    Uploading: http://maven.jenkins-ci.org:8081/content/repositories/releases/org/jenkins-ci/plugins/sinatra-chef-builder/1.4/sinatra-chef-builder-1.4.hpi
    Uploading: http://maven.jenkins-ci.org:8081/content/repositories/releases/org/jenkins-ci/plugins/sinatra-chef-builder/1.4/sinatra-chef-builder-1.4.pom
    [INFO] ------------------------------------------------------------------------
    [INFO] BUILD FAILURE
    [INFO] ------------------------------------------------------------------------
    [INFO] Total time: 01:07 min
    [INFO] Finished at: 2017-01-09T04:03:04-08:00
    [INFO] Final Memory: 53M/461M
    [INFO] ------------------------------------------------------------------------
    [WARNING] The requested profile "jenkins-release" could not be activated because it does not exist.
    [ERROR] Failed to execute goal org.apache.maven.plugins:maven-deploy-plugin:2.6:deploy (default-deploy) on project sinatra-chef-builder: Failed to deploy artifacts: Could not transfer artifact org.jenkins-ci.plugins:sinatra-chef-builder:hpi:1.4 from/to maven.jenkins-ci.org (http://maven.jenkins-ci.org:8081/content/repositories/releases): Connect to maven.jenkins-ci.org:8081 [maven.jenkins-ci.org/199.193.196.24] failed: Connection timed out: connect -> [Help 1]
    [ERROR]
    [ERROR] To see the full stack trace of the errors, re-run Maven with the -e switch.
    [ERROR] Re-run Maven using the -X switch to enable full debug logging.
    [ERROR]
    [ERROR] For more information about the errors and possible solutions, please read the following articles:
    [ERROR] [Help 1] http://cwiki.apache.org/confluence/display/MAVEN/MojoExecutionException
[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 01:24 min
[INFO] Finished at: 2017-01-09T04:03:04-08:00
[INFO] Final Memory: 20M/269M
[INFO] ------------------------------------------------------------------------
[ERROR] Failed to execute goal org.apache.maven.plugins:maven-release-plugin:2.5.3:perform (default-cli) on project sinatra-chef-builder: Maven execution failed, exit code: '1' -> [Help 1]
[ERROR]
[ERROR] To see the full stack trace of the errors, re-run Maven with the -e switch.
[ERROR] Re-run Maven using the -X switch to enable full debug logging.
[ERROR]
[ERROR] For more information about the errors and possible solutions, please read the following articles:
[ERROR] [Help 1] http://cwiki.apache.org/confluence/display/MAVEN/MojoExecutionException


now , i am not getting why the port is coming as 8081 eventhough nothing is there in effective POM as such