Availability: default
In terms of GoGrid sandbox server is a server which will be used as a base for some server image. It can be created by passing extra argument ex_issandbox like that:
$ lc-node-add -s 1GB -i 123 -n mysandbox ex_issandbox=true
The created server will be a sandbox server.
Please refer to http://wiki.gogrid.com/wiki/index.php/MyGSIGoGrid wiki to get more details on sandboxes and server images.