[Swan-dev] setting up tests on a brand new Fedora 23 installation

D. Hugh Redelmeier hugh at mimosa.com
Wed May 18 14:42:38 UTC 2016

| From: D. Hugh Redelmeier <hugh at mimosa.com>

| qemu-img create -F qcow2 -f qcow2 -b '/home/build/pool/swanfedorabase.qcow2' '/home/build/pool/east.qcow2'
| qemu-img: /home/build/pool/east.qcow2: Could not open '/home/build/pool/swanfedorabase.qcow2': No such file or directory
| /home/build/libreswan/mk/kvm-targets.mk:420: recipe for target '/home/build/pool/east.qcow2' failed
| make: *** [/home/build/pool/east.qcow2] Error 1
| I don't know why that would happen.  Andrew?

We (Andrew and I) figured out the problem.  Not enough entropy on my
system so the step was blocking on getting random numbers and timing out.

It would be nice if the symptom more clearly pointed to the disease!

I've figured out how to get more entropy on my system and tests are
running as I type this.  I'll write up the magic later.

Summary of magic:

- my computer is too old to have the RdRand feature.  Intel processors
  of the "Ivy Bridge" generation or later have it.  Newer AMD
  processors have it too.  If /proc/cpuinfo has "rdrand" then the
  processor has this feature.  Some people worry that rdrand supplies
  random numbers that three-letter-agencies know too much about.

- my computer does have a TPM device and that can be a source of
  entropy.  But it needs some poorly documented configuring to work.
  Worries about insecurity apply here to.

- if you have neither of those, you have to work harder to get entropy.
  Like wave your mouse around a lot.  Or use fake entropy.

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