Maven - how to solve an error when downloading from a repository?

Question

Java

In intellij Idea, I created a maven project, when compiling, or when executing a command via CMD maven install,
it gives the following error

[INFO] Scanning for projects...
[WARNING] 
[WARNING] Some problems were encountered while building the effective model for com.springapp:Matorin_req:war:1.0-SNAPSHOT
[WARNING] 'build.plugins.plugin.version' for org.apache.maven.plugins:maven-compiler-plugin is missing. @ line 64, column 21
[WARNING] 'build.plugins.plugin.version' for org.apache.maven.plugins:maven-surefire-plugin is missing. @ line 71, column 21
[WARNING] 
[WARNING] It is highly recommended to fix these problems because they threaten the stability of your build.
[WARNING] 
[WARNING] For this reason, future Maven versions might no longer support building such malformed projects.
[WARNING] 
[INFO] 
[INFO] Using the builder org.apache.maven.lifecycle.internal.builder.singlethreaded.SingleThreadedBuilder with a thread count of 1
[INFO]                                                                         
[INFO] ------------------------------------------------------------------------
[INFO] Building Matorin_req 1.0-SNAPSHOT
[INFO] ------------------------------------------------------------------------
Downloading: http://repo.maven.apache.org/maven2/org/apache/maven/plugins/maven-resources-plugin/2.6/maven-resources-plugin-2.6.pom
июл 25, 2014 10:31:08 AM org.apache.maven.wagon.providers.http.httpclient.impl.execchain.RetryExec execute
INFO: I/O exception (java.net.SocketException) caught when processing request: Network is unreachable: connect
июл 25, 2014 10:31:08 AM org.apache.maven.wagon.providers.http.httpclient.impl.execchain.RetryExec execute
INFO: Retrying request
июл 25, 2014 10:31:29 AM org.apache.maven.wagon.providers.http.httpclient.impl.execchain.RetryExec execute
INFO: I/O exception (java.net.SocketException) caught when processing request: Network is unreachable: connect
июл 25, 2014 10:31:29 AM org.apache.maven.wagon.providers.http.httpclient.impl.execchain.RetryExec execute
INFO: Retrying request
июл 25, 2014 10:31:50 AM org.apache.maven.wagon.providers.http.httpclient.impl.execchain.RetryExec execute
INFO: I/O exception (java.net.SocketException) caught when processing request: Network is unreachable: connect
июл 25, 2014 10:31:50 AM org.apache.maven.wagon.providers.http.httpclient.impl.execchain.RetryExec execute
INFO: Retrying request
[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 01:24 min
[INFO] Finished at: 2014-07-25T10:32:11+04:00
[INFO] Final Memory: 4M/15M
[INFO] ------------------------------------------------------------------------
[ERROR] Plugin org.apache.maven.plugins:maven-resources-plugin:2.6 or one of its dependencies could not be resolved: Failed to read artifact descriptor for org.apache.maven.plugins:maven-resources-plugin:jar:2.6: Could not transfer artifact org.apache.maven.plugins:maven-resources-plugin:pom:2.6 from/to central (http://repo.maven.apache.org/maven2): Network is unreachable: 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/PluginResolutionException

Before that everything was fine.

Answer 1

Plugin org.apache.maven.plugins:maven-resources-plugin:2.6 is not available or the library from its dependencies is not available.
See what's wrong with this plugin, did the version change, is it available in the turnip, etc.