Question

I want to share my experience of using maven through a proxy.

You would most likely face exceptions and messages like:

repository metadata for: 'org.apache.maven.plugins' could not be retrieved from 
repository: central due to an error: Error transferring file: Connection refused: connect

or

[WARNING] Failed to retrieve plugin descriptor for org.apache.maven.plugins:maven-clean-
plugin:2.5: Plugin org.apache.maven.plugins:maven-clean-plugin:2.5 or one of its 
dependencies could not be resolved: Failed to read artifact descriptor for 
org.apache.maven.plugins:maven-clean-plugin:jar:2.5

How to configure Maven to use proxy server?

Answer 1

Those are caused most likely by 2 issues:

1. You need to add proxy configuration to your settings.xml. Here’s a trick in your username field. Make sure it looks like domain\username. Setting domain there and putting this exact slash is important ‘\’. You might want to use <![CDATA[]]> tag if your password contains non xml-friendly characters.
2. I’ve noticed maven 2.2.0 does not work sometimes through a proxy at all, where 2.2.1 works perfectly fine.

If some of those are omitted – maven could fail with random error messages.

Just hope I’ve saved somebody from googling around this issue for 6 hours, like I did.