I use the following configuration in .m2/settings.xml to forward all request to an internal repository:
<settings xmlns="http://maven.apache.org/SETTINGS/1.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/SETTINGS/1.0.0
http://maven.apache.org/xsd/settings-1.0.0.xsd">
<localRepository>/home/bozhidar/.m2/repository</localRepository>
<interactiveMode>true</interactiveMode>
<offline>false</offline>
<servers>
<server>
<id>nexus</id>
<username>***</username>
<password>***</password>
</server>
</servers>
<mirrors>
<mirror>
<!--This sends everything else to /public -->
<id>nexus</id>
<mirrorOf>*</mirrorOf>
<url>https://xxx/nexus/content/groups/public</url>
</mirror>
</mirrors>
<profiles>
<profile>
<id>nexus</id>
<!--Enable snapshots for the built in central repo to direct -->
<!--all requests to nexus via the mirror -->
<repositories>
<repository>
<id>central</id>
<url>http://central</url>
<releases>
<enabled>true</enabled>
</releases>
<snapshots>
<enabled>true</enabled>
</snapshots>
</repository>
</repositories>
<pluginRepositories>
<pluginRepository>
<id>central</id>
<url>http://central</url>
<releases>
<enabled>true</enabled>
</releases>
<snapshots>
<enabled>true</enabled>
</snapshots>
</pluginRepository>
</pluginRepositories>
</profile>
</profiles>
<activeProfiles>
<!--make the profile active all the time -->
<activeProfile>nexus</activeProfile>
</activeProfiles>
</settings>
Btw, I've used Archiva in the past and I can recommend you to try out Sonatype Nexus or Artifactory - they are both free and both much nicer than Archiva.