setting up secure tmpfs in fstab

Solution 1:

The first field is the storage backend you want to mount. In case of tmpfs, there is none storage backend.

From man fstab

The first field (fs_spec).
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For filesystems with no storage, any string can be used, and will show up in df(1) output, for example. Typical usage is proc for procfs; mem, none, or tmpfs for tmpfs.
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