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    SubjectRe: Seeding /dev/random not working

    > > I have two embedded boards (one ARM, one PowerPC), running two
    > > different versions of 2.6. They have no hard drives, keyboards or
    > > mice. They each have a NIC, but I understand these make no
    > > contribution to the entropy pool.
    > >
    > > if [ -f $random_seed ]; then
    > > cat $random_seed >/dev/urandom # should seed the pool
    > > fi
    > > dd if=/dev/urandom of=$random_seed count=1 2>/dev/null # save some
    > > data from urandom for next boot
    > >
    > > I have rebooted my boards many times, and after each boot I read the
    > > contents of $random_seed. Whilst it does not happen every time, the
    > > contents of $random_seed are /often the same/. To give you a feel:
    > > rebooted 11 times, got a total of 3 different outputs.
    > Ok, so this is telling me a couple of things. First of all, if you're
    > only getting three outputs, it means that you don't have any
    > peripherals feeding entropy into the system from the boot sequence.
    > Without any hard drives, keyboards or mice, and a NIC whose device
    > driver hasn't been configured to feed entropy, you're definitely
    > hosed.

    Can we get at least time-of-boot from rtc clock to the pool? We really
    should not be getting identical outputs...

    (cesky, pictures)
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      Last update: 2007-05-29 16:17    [W:0.019 / U:8.356 seconds]
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