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Comment by onemorepassword | Hacker News Reader

Excuse my ignorance, but this is a desktop tool. How does a single desktop machine have hundreds or users and groups?

A common pattern in administering large Linux workstation installations is having the machines poll a central user database which generates new group/password files. Of course ideally you can pull a subset, but if everyone needs to be able to log into that workstation, then everyone needs to be in /etc/passwd. There are other solutions, but this is a simple and effective one that means most people can still log in if your authentication servers are down.

Why do hundreds of people log into one workstation? Or do you mean each person to their own workstation, but they all share a common passwd file?

One example where hundreds of people need to be able to physically log into a single workstation is an educational computer lab where you have a 20 or so shared workstations, and requiring assigned seating would be cumbersome. Having a common passwd file for personal workstations is also an understandable configuration for ease of administration, though it of course has its drawbacks.

Imagine a company with 100 employees, and 100 shared workstations.

Now imagine everyone has to be able to log on to each workstation.

In our case we run servers and then have thin desktops (using LTSP) that actually log in and run their sessions on the servers. The servers carry our entire password and group file because everyone can log in to them.

In general, in any NFS based environment all machines that NFS-mount common filesystems need to carry a full collection of login and group information so that things like 'ls -l' work on the NFS filesystems. If you want everyone to be able to log into every machine, they also need some sort of password information as well (either by distributing shadow files or by various other means).

Why do people use NFS in this decade, when we have stuff like FUSE to put a file API on top of reliable networking tools?

NFS is an unstable buggy mess suitable only for light personal use. I have never been at an org that wasn't actively migrating off of legacy NFS , and that ended years ago.

Our experience is that NFS works excellently in the environment it was designed for (a LAN environment of Unix machines administered by the same people). I still haven't seen a better Unix remote filesystem (and most of the modern distributed filesystem efforts are solving different problems, as seen by the fact that they don't support full core Unix semantics).

With that said, the environment NFS was designed for is increasingly uncommon. NFS is not necessarily a good fit for other environments, even if they look superficially similar.

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