npm ERR! Linux 4.1.19-boot2docker
npm ERR! argv "/usr/local/bin/node" "/usr/local/bin/npm" "i" "webpack" "-SD"
npm ERR! node v5.9.0
npm ERR! npm  v3.8.3
npm ERR! path ../esprima/bin/esvalidate.js
npm ERR! code EPROTO
npm ERR! errno -71
npm ERR! syscall symlink

npm ERR! EPROTO: protocol error, symlink '../esprima/bin/esvalidate.js' -> '/var/www/node_modules/.bin/esvalidate'
npm ERR!
npm ERR! If you need help, you may report this error at:
npm ERR!     <https://github.com/npm/npm/issues>

npm ERR! Please include the following file with any support request:
npm ERR!     /var/www/npm-debug.log

解决方案：

npm i webpack -g –no-bin-links

–no-bin-links tells npm to not create any symbolic links. There isn’t a way (to my knowledge) of translating symlinks to a Windows share.