Port 2049: NFS
Port 2049 is NFS, the network file-sharing protocol used mostly by Linux and Unix systems.
What runs on port 2049
NFS servers export folders that other machines mount as if they were local disks, over port 2049. It was created by Sun in the 1980s. Older versions rely on the portmapper on 111 and trust client IP addresses rather than user logins.
On a home network
NAS boxes with NFS enabled, Linux home servers and some media players that mount NFS shares use 2049. Many NAS devices ship with NFS off.
If port 2049 is reachable from the internet
NFS should never be reachable from the internet. Exports are often protected only by the client's IP address, so a misconfigured export can be mounted and read or modified by anyone who can reach it.
How to check whether it is open on your network
In your NAS file services, check whether NFS is enabled and which hosts each export allows. Confirm no router rule forwards 2049 or 111.
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