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Am Donnerstag, 20. Dezember 2012, 11:45:34 schrieb Mark David Dumlao: |
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> On Thu, Dec 20, 2012 at 2:42 AM, Volker Armin Hemmann |
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> |
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> <volkerarmin@××××××××××.com> wrote: |
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> > with redhat's push to move everything into /usr - why not stop right there |
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> > and move everything back into /? |
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> |
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> I originally thought this way, but they actually reviewed the |
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> technical and historical merits for all the use cases and and found |
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> /usr to be superior. Straight out of the freedesktop wiki: |
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> http://www.freedesktop.org/wiki/Software/systemd/TheCaseForTheUsrMerge |
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> |
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> 0) If / and /usr are kept separate, programs in /usr can't be updated |
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> independently of programs in /, because the libraries they depend on |
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> might break compatibility. If the binaries and libraries were *all* in |
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> /usr, then the entire system's binaries would always be consistent |
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> regardless of where /usr were sourced from (config files in /etc, |
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> however, would still break). |
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not a problem at all if everything is in / and /usr doesn't even exist |
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anymore. |
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> 1) There is historical precedent in Unix for /usr-centric systems, |
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> notably Solaris. |
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so what? historically we lived in mud huts and used flintstone knives. |
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> 2) If /usr were separated from /, then /usr could be mounted |
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> read-only, with / being mounted "normally". Which makes sense, as / |
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> does have bits that are meant to be read-write. |
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really? once upon a time I was told mounting / ro and /usr rw was a GOOD THING |
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to do. I ignored that the same way I ignore it the other way round. With bind |
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mounting and stuff, you can make single directories rw.. so what is the matter? |
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> 3) Most software packagers write their binaries to a PREFIX defaulting |
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> to /usr/local, or /usr, as opposed to /. Determining which ones belong |
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> in / or /usr can sometimes be dependent on the distro and/or sysad. |
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> But since more of them default to /usr, if everything were in /usr |
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> it'd be a saner default. |
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so what? PREFIX can be changed. Set it to /local if you want. Or /var/local. |
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Or /my/happy/place/local. |
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> |
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> (0) basically says that keeping them separate only works as intended |
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> if the both the sysad and the distro upstream work together for their |
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> shared /usr mount. In many cases, however, sysads have to do a lot of |
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> working around and careful planning to get /usr mounted remotely. |
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> (1), (2), and (3) provide advantages to mounting the binaries and |
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> libraries separately from the / filesystem, which mounting them as |
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> part of / does not provide. |
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no, not really. No. |
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-- |
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#163933 |
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