Messages in this thread | | | Subject | Re: udev and devfs - The final word | From | Rob Love <> | Date | Thu, 01 Jan 2004 10:22:53 -0500 |
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On Thu, 2004-01-01 at 07:34, Rob Landley wrote:
> Fundamental problem: "Unique" depends on the other devices in the system. You > can't guarantee unique by looking at one device, more or less by definition.
Of course.
> Combine that with hotplug and you have a world of pain. Generating a number > from a device is just a fancy hashing function, but as soon as you have two > devices that generate the same number independently (when in separate > systems) and you plug them both into the same system: boom.
A solution would have to deal with collisions.
> Of course the EASY way to deal with collisions is to just fail the hash thingy > in a detectable way, and punt to some kind of udev override. So if you yank > a drive from system A, throw it in system B, try to re-export it NFS, and > it's not going to work, it TELLS you.
No no no. Nothing this complicated. No punting to udev.
> Solve 90% of the problem space and have a human deal with the exceptions. How > big's the unique number being exported, anyway? (If it's 32 bits, the > exceptions are 1 in 4 billion. It may never be seen in the wild...)
Device numbers are 64-bit now.
Rob Love
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