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If you want to ensure well working failover you must, at some point,
test it. Even better, you may want to regularly test it (check out
Netflix's Chaos Monkey). <br>
<br>
One way to run a simulation would be to use a firewall rule or
static route to block access between your test client/recursive
server and one or more of the authoritative DNS servers. However,
this is no substitute for an actual test to determine how different
client applications will behave.<br>
<br>
--Blake<br>
<br>
<br>
<div class="moz-cite-prefix">Sid Shapiro wrote the following on
6/9/2014 4:56 PM:<br>
</div>
<blockquote
cite="mid:CAJYWScakoEyyFr-UFVkiSD_2QyVMCjsfkinvEQZ+-ZOVdcLp3g@mail.gmail.com"
type="cite">
<div dir="ltr">Again - thanks for the quick response - that'll
teach me to post without all the facts. I simply don't remember
what the specific error was, darn it. It might have been
NXDOMAIN or SERVFAIL - I didn't write it down.
<div>
The test I was running was on a barely, if ever used, domain,
so I was pretty sure it wasn't cached anywhere.</div>
<div><br>
</div>
<div>I'm trying to figure out ways to test this without taking
name servers offline :-)</div>
</div>
<div class="gmail_extra"><br clear="all">
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<div dir="ltr">
<div>--</div>
<div>Sid Shapiro
<a moz-do-not-send="true"
href="mailto:sid_shapiro@bio-rad.com" target="_blank">sid_shapiro@bio-rad.com</a><br>
</div>
<div>Bio-Rad Corporate IT - Desk: (510) 741-6846 Mobile:
(510) 224-4343</div>
</div>
</div>
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