node-gyp: Not able to install using npm because of (node-gyp rebuild) in Ubuntu 12.04 LTS running on free tier Amazon EC2 Instance

npm install exec-sync
npm http GET https://registry.npmjs.org/exec-sync
npm http 200 https://registry.npmjs.org/exec-sync
npm http GET https://registry.npmjs.org/exec-sync/-/exec-sync-0.1.4.tgz
npm http 200 https://registry.npmjs.org/exec-sync/-/exec-sync-0.1.4.tgz
npm http GET https://registry.npmjs.org/ffi/1.0.1
npm http 200 https://registry.npmjs.org/ffi/1.0.1
npm http GET https://registry.npmjs.org/ffi/-/ffi-1.0.1.tgz
npm http 200 https://registry.npmjs.org/ffi/-/ffi-1.0.1.tgz
npm http GET https://registry.npmjs.org/bindings
npm http GET https://registry.npmjs.org/debug
npm http GET https://registry.npmjs.org/ref
npm http GET https://registry.npmjs.org/ref-struct
npm http 200 https://registry.npmjs.org/bindings
npm http GET https://registry.npmjs.org/bindings/-/bindings-1.0.0.tgz
npm http 200 https://registry.npmjs.org/debug
npm http GET https://registry.npmjs.org/debug/-/debug-0.7.0.tgz
npm http 200 https://registry.npmjs.org/ref-struct
npm http GET https://registry.npmjs.org/ref-struct/-/ref-struct-0.0.3.tgz
npm http 200 https://registry.npmjs.org/ref
npm http GET https://registry.npmjs.org/ref/-/ref-0.1.2.tgz
npm http 200 https://registry.npmjs.org/bindings/-/bindings-1.0.0.tgz
npm http 200 https://registry.npmjs.org/ref-struct/-/ref-struct-0.0.3.tgz
npm http 200 https://registry.npmjs.org/debug/-/debug-0.7.0.tgz
npm http 200 https://registry.npmjs.org/ref/-/ref-0.1.2.tgz

> ref@0.1.2 install /root/node/node_modules/exec-sync/node_modules/ffi/node_modules/ref
> node-gyp rebuild

gyp WARN install got an error, rolling back install
gyp ERR! configure error 
gyp ERR! stack Error: EACCES, stat '/root/.node-gyp/0.8.6'
gyp ERR! System Linux 3.2.0-25-virtual
gyp ERR! command "node" "/usr/local/lib/node_modules/npm/node_modules/node-gyp/bin/node-gyp.js" "rebuild"
gyp ERR! cwd /root/node/node_modules/exec-sync/node_modules/ffi/node_modules/ref
gyp ERR! node -v v0.8.6
gyp ERR! node-gyp -v v0.6.3
gyp ERR! not ok 
npm ERR! ref@0.1.2 install: `node-gyp rebuild`
npm ERR! `sh "-c" "node-gyp rebuild"` failed with 1
npm ERR! 
npm ERR! Failed at the ref@0.1.2 install script.
npm ERR! This is most likely a problem with the ref package,
npm ERR! not with npm itself.
npm ERR! Tell the author that this fails on your system:
npm ERR!     node-gyp rebuild
npm ERR! You can get their info via:
npm ERR!     npm owner ls ref
npm ERR! There is likely additional logging output above.

npm ERR! System Linux 3.2.0-25-virtual
npm ERR! command "/usr/local/bin/node" "/usr/local/bin/npm" "install" "exec-sync"
npm ERR! cwd /root/node
npm ERR! node -v v0.8.6
npm ERR! npm -v 1.1.48
npm ERR! code ELIFECYCLE
npm ERR! 
npm ERR! Additional logging details can be found in:
npm ERR!     /root/node/npm-debug.log
npm ERR! not ok code 0