[master] servfail cache

3943.	[func]		SERVFAIL responses can now be cached for a
			limited time (configured by "servfail-ttl",
			default 10 seconds, limit 30). This can reduce
			the frequency of retries when an authoritative
			server is known to be failing, e.g., due to
			ongoing DNSSEC validation problems. [RT #21347]

bin/tests/system/sfcache/prereq.sh

@@ -0,0 +1,25 @@
+#!/bin/sh
+#
+# Copyright (C) 2014  Internet Systems Consortium, Inc. ("ISC")
+#
+# Permission to use, copy, modify, and/or distribute this software for any
+# purpose with or without fee is hereby granted, provided that the above
+# copyright notice and this permission notice appear in all copies.
+#
+# THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
+# REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
+# AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
+# INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
+# LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
+# OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+# PERFORMANCE OF THIS SOFTWARE.
+
+../../../tools/genrandom 400 random.data
+
+if $KEYGEN -q -a RSAMD5 -b 512 -n zone -r random.data foo > /dev/null 2>&1
+then
+    rm -f Kfoo*
+else
+    echo "I:This test requires that --with-openssl was used." >&2
+    exit 1
+fi