How does Isilon SnapshotIQ use storage for snapshots?

A customer wishes to back up their Isilon cluster via NDMP using a software package that supports NDMP connectivity. The backup process will require the cluster to create a point-in-time copy of the directory to be backed up.
Which OneFS feature(s) will need to be licensed?

When designing Isilon solutions, what issues should you pay special attention to?

You are asked to size a cluster for a file sharing environment. nfsstat indicates that 75% of the requests are namespace operations (e.g., GETADDR, SETADDR). There will be 8,000 active Linux users, connecting over NFS.
Which cluster configuration would you recommend?

If Isilon SmartConnect is being configured in a customer environment, which records are required for a supported implementation?