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[Xen-devel] [PATCH] Really randomize generated MAC addresses

from [James Dykman]

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Subject:	[Xen-devel] [PATCH] Really randomize generated MAC addresses
From:	James Dykman <dykman@xxxxxxxxxx>
Date:	Tue, 16 Aug 2005 14:48:29 -0400
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Randomly generated vif MAC addresses are decidedly non-random..... 
duplicate even. I tracked it down to the PRNG being re-seeded
with the same seed (the current timestamp) for each vif.

Jim


# HG changeset patch
# User Jim Dykman dykman@xxxxxxxxxx
# Node ID 06be64b17a136d2d6029b500611e32199b8065f1
# Parent  3d187585c1415fbb14cb285cc71e0ff0faf81e67


Really randomize generated MAC addresses
random.seed() uses the timestamp as a new seed and we're calling
randomMAC faster than the timestamp changes, resulting in duplicate MACs.

Signed-off-by: Jim Dykman <dykman@xxxxxxxxxx>

diff -r 3d187585c141 -r 06be64b17a13 tools/python/xen/xm/create.py
--- a/tools/python/xen/xm/create.py     Tue Aug 16 11:20:47 2005
+++ b/tools/python/xen/xm/create.py     Tue Aug 16 17:07:25 2005
@@ -380,7 +380,6 @@

     @return: MAC address string
     """
-    random.seed()
     mac = [ 0xaa, 0x00, 0x00,
             random.randint(0x00, 0x7f),
             random.randint(0x00, 0xff),


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