Mirroring Callisto Update Site
It is possible to make a local mirror of all Callisto update site with a little known command:
java -jar startup.jar -application org.eclipse.update.core.standaloneUpdate -command mirror -from http://download.eclipse.org/callisto/releases -to c:\eclipse-mirror -mirrorURL http://your.local.domain
Run this command from Eclipse install directory (i.e. where startup.jar is).
Replace "c:\eclipse-mirror" with the local directory where the update site contents will be copied to, and [...]