Suppose the following setup:

• local network behind a proxy
• one "remote repository" running on a local machine, mirror of ibiblio
• Maven builds get the resources from the above "remote repository", hence no need for proxy settings in the projects. Actually, setting a proxy would only slow things down.

When running "site:generate" linkcheck kicks in, but sees no proxy and fails trying to reach outside links like "http://maven.apache.org/".

If we set a proxy the general build process is slowed unnecessarily.
If not, goals like "site:generate" are slooooow to run due to timeouts in linkcheck.

AFAIK there is no (obvious/direct/simple) way to have "no proxy" when building and "some proxy" when linkchecking.

Suggestion 1:
allow linkcheck to use its own set of proxy settings if the "normal" ones are not found. Some property like "maven.linkcheck.proxy.host=192.168.0.1".

Suggestion 2:
Use automatically proxy settings from the environment (global env, not Maven's). These would be users's settings for browsing the Net anyway, so these are probably the best choice anyway.