NFS (Network File System) exports a directory tree from a server so that clients can mount it as if it were a local filesystem. RHCSA requires you to know how to mount a pre-existing NFS export on a client — and increasingly, to understand the export side enough to verify it's working.
The simulator now models both sides. The Mastery tab includes multi-host tasks where you run exportfs on server2 and mount -t nfs on server1, with the validator checking both engines.
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