Filesystem Hierarchy Standard - Reference Poster / Cheatsheet
Hey, I've recently designed a Poster about the FHS since I often forget where I should place or find things. Do you have any feedback how to make it better?
I updated the poster: https://whimsical.com/fhs-L6iL5t8kBtCFzAQywZyP4X use the link to see online.
Dark mode
Old version
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Done!
Damn that's some great work ! When I started linux I wish I had found such ressources, I was really curious what each of these directories were for.
Would you mind if your material was reused (with credit) for education purposes ?
I'd be more than happy if this was used. Do whatever you want with it as long as you abide by the CC BY-SA-4.0 license. This means you can share freely and modify as long as you keep the authorship information and share with same license.
The FHS was started in 1994 and is free to use. It should be used now by all major Linux systems and most Unix too.
The only credit is to the Linux Foundation.
Related: man hier
it bothers me a little the entry is not called fhs: man fhs
Added to new version. Thanks for the suggestion.
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I just mount mine into /mnt and bind mount subdirectories from them into wherever I need the space.
Edit: if you want a more theoretically correct location according to the FHS you could mount drives somewhere under /run and bind their contents from there. I've done that before as well.
tbh I don't think it matters, so wherever you feel like doing it. I just leave it where the distro or file manager defaults to: in Ubuntu-based distros that's /media/$USER/mount-name. For mounts shared across users you could drop the $USER.
Since FHS doesn't specify where "non-removable media" should go, I don't think it makes sense to adopt this recommendation as "/media should be removable", but rather, "in case the media IS removable, then mount it to /media/".
If they are internal and permanent (read: unlikely to be removed on a daily basis), I'd just mount them based on their purpose and not them being separate HDDs physically. If they are meant for logs, mount them at /var/log. If they are meant for your movies, /home/user/data is more than fine. In general FHS describes the directory hierarchy, not which parts of it are mountpoints and which are physically on the same media. Technically you're fine having each and every directory on a separate HDD.
I'm also mounting them into /home/user/data while I don't think hard-coding the user name in the mountpoint is a good idea. Besides, it needs the assumption that I'm the only "human-user" of this computer.
I may also mount them at /opt/data, but I'm not sure if it's a good idea
From my humble knowledge I would suggest /var/opt/XXX. It's the variable part of the /opt hierarchy.
I’m coming more from a server perspective but, fundamentally, all HDDs are “temporary”. Eventually that data might be in a bigger/faster/functioning replacement - so it’s best to treat the drive as something which can always be replaced.
Continuing that, you might mount to /mnt and then symlink that where you really want it, say ../games. That layer of abstraction allows you to replace the drive without much effect on install. Also allows for expansion via something like mergerfs (*no idea if that’s a good idea for your use cases)
I originally had mine mounted on /, to make them easy to type. But that set one of my highly opinionated friends wretching, so I re-mounted them to /media// to placate him and symlinked them to my home directory instead.
It's frustrating how often Linux systems, when approached with a "where is the canonical location for ?" question, have an answer ancient use cases practically no one has anymore, but no satisfying answer for extremely common use cases like permanently mounted backup drives, where to put web server hosted files, or even where to install applications that don't come from package managers (/opt/? /usr/bin/? /home//.local/?).
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If it's just personal files and backups, there's absolutely nothing wrong with what you're doing.
If you had, say, active system config files there, it would make things... complicated to say the least.
Not sure if this is proper procedure since I searched around and didn't find much, but I've got an internal drive just for games mounted at /home/games. Haven't had any issues so far.
Usb devices are nowadays when connected mounted somewhere in /run/%user
I really like this, but can I have a black background version please?
You could invert the colors in GIMP or similar.
That wouldn't look as good tho. I want the black text to be white and the white background to be black not invert everything.
We need something like this for home, I hate that programs like steam and firefox place themselves directly into home instead of ~/.config and ~/.llocal.
I even move my personal themes to /usr/share/themes because not everything works with ~/.local/share/themes and needs a ~/themes directory instead.
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Thunderbird isn't really developed by Mozilla any more. It's owned by a subsidiary of Mozilla and is mostly community-run.
Super useful, thanks. Actually made a lot of things click in my head about how Linux works.
When did /home get deprecated? Is /usr/local the replacement?
Sorry for the n00b question (I'm not a noob, but I have been off Linux for a few years), figured the answer may be useful to other users too
/home is not deprecated, it's optional but common. Here is the section from FHS: https://refspecs.linuxfoundation.org/FHS_3.0/fhs/ch03s08.html
then the legend should be fixed its confusing, as is the whole idea of FHS is outdated and a chore for new users to get into (i still don't fully understand it)
This is a very useful, very well done chart, congratulations.
But what a mess is FHS. Easily the worst thing of linux design for me
The better you understand it the less it seems bad.
I don't understand the ambiguity of where to put your projects.
I've typically always put things under /opt/ TIL /etc/opt was where the config should go.
Depends on the scope of your project. But if they are services for example or you want them to be run by different users on the system, you could either use /opt or /usr/local. There is some discussion about which is better or how to choose: eg. https://www.linuxjournal.com/magazine/pointcounterpoint-opt-vs-usrlocal . The FHS is mostly relevant when packaging your software though.
Great but what I'm missing is the information that "usr" does not stand for "user", like many people think or even say. If it would the name could actually be "user" and not "usr".
The chart actually does not say what exactly it stands for. It's "user resources" AFAIK.
It's worth clearing this up in my opinion.
Thanks for the input. Things are complicated: https://askubuntu.com/a/135679 . Apparently it originally meant "user" but then slowly was used for system stuff. So people invented backcronyms.
That's just retconning/backronyming it.
/usr does historically stand for user. It's where the user home directories were on old Unix versions.
laughs in guix
does guix go the same was as nixos in that regard? where can I find info regarding FHS in guix?
Afaik guix is very similar to nixos in that respect. The store where applications are installed is called /gnu there.
yeah it uses /gnu instead of /nix
FHS? Who needs that?
how is /usr/local local and not system-wide? i though it was for programs you compiled yourself?
"Local" in this context means local to this whole machine. From the perspective of a single user, it's system-wide. But then from the perspective of a sysadmin managing dozens of such systems, it's local.
thanks for the explanation!
Many FHS things don't make much sense for single-user (human user) systems on modern hardware. /usr/local does though. It's for you (as admin) to install software that doesn't come with the os.
Nicely done! Do you perchance have any hi res version?
Thanks! Unfortunately I've used closed source whimsical.com for this and don't have a paid subscription. They only offer low-res for those accounts since recently :(
Maybe try to do inkscape?
Maybe some AI upscaling could do the trick ?
perchance
Laughs in Nix
well nix still uses the same structure, the only difference is that files are symlinked to files in subfolders of the /nix/store folder.
For example you may find that /etc/hosts is just a symlink to /nix/store/69420aaabbbcccdddfffggghhhiii420-hosts
I've never seen /etc/opt used. Usually if an app is in /opt, the entire app is there, including its config which is frequently at /opt/appname/etc/.
Quest One Identity does.
/opt is kinda legacy at this point. That used to be the location where you'd install software manually in the past but I haven't seen it used for some time, it was more common in the 00's.
I still put all my standalone apps in there (meaning apps that are often statically compiled and expect the executable, logs, and config to be in the same directory), as well as apps that have their own docker-compose.yml file. Should I be putting them somewhere else? I know /srv exists but I've never used it and I don't think Debian creates it by default.
Looks great!
And /net is usually autofs mounted.
That's NFS shares? I might add that later although it's not very common or standard I guess. Thx
Yeah, nfs exports that can be mounted by HOSTNAME or ip address automatically with autofs. Sorry if that’s not standard, like my other comment about /mnt. I’ve never actually looked at the spec. I was just giving feedback based on what I’ve seen in the industry. So might not be spec compliant but a lot of it is common practice I’ve seen (for better or worse.)
What do you mean by locally vs site wide? For /usr/local that’s usually stuff installed from outside of the distributions normal packaging mechanism. E.g. if you build something from source using “make”, the “make install” would install it there by default (though that is also configurable.)
Also not sure we want to say /mnt is necessarily temporary. Any mount pionts there could easily be added to fstab.
The FHS says the thing about /mnt. It's not normally meant to have subdirectories or be mounted to by default.
The origin is that /usr may be network mounted or otherwise shared across multiple systems, whereas /usr/local is local to a particular PC. That definition is not as relevant with today's single-user machines, and now it mostly means what you said (/usr is managed by system package manager whereas /usr/local is manually managed).
What would a use case be for
>/usr/bin
versus
/usr/local/bin
Binaries in the former are installed by the OS/package manager, binaries in the latter are installed manually by the user, for example by compiling from source and running make install
Great. Now I gotta refactor some scripts.
