[Autogenerated] we've already seen what
silence looks like you have a request, and
then either literally silence or an ICMP
are message. Either way, you don't have
the DNAs response you're looking for. But
let's look deeper into Jaden's trace file
to see what else we confined. When there's
silence, will filter for DNA's first, then
opened the expert by clicking on the
circle in the lower left hand corner. Now,
if we say limit to display filter, we're
only looking at the errors specific. 2D
NetBeans. We have retransmissions both for
the responses and for the queries. If we
expand the warnings, we can tell not only
what packet numbers are involved, but what
the queries and query responses were for.
If I click on one of the warnings, notice
it jumps right to pack it. 58 79. A query
for the A record for w w w dot Pluralsight
dot com wires. Shark uses the transaction
ID to correlate the request and the reply.
If I filter based on that transaction, ID
I can focus on just this query. That's one
of those context sensitive filters.
Whatever packet you're on when you click
on the DNAs transaction IDE button you'll
get all packets that have that same
transaction. ID we can. See where Jaden
made the request to the N s stub server.
Received silence. Tried again after a
second. Still silence tried again. Still
silence. Then waited two seconds just to
be sure. And that time he actually got a
reply. Now, remember all of that time the
service was stopped on N s primary, where
shark calculates forest the time in
between the first request On the first
reply, it took the server 4.96 seconds to
send that reply. When the reply came back,
we had a canonical name record. W w dot
Pluralsight dot com is actually an alias
that is farmed out to the content delivery
network. That's what the cdn always stand
for for Cloudflare .NET. And then we have
our two IP addresses for that server.
Let's filter by that expert are message
Ford nested retransmissions. I'm not
interested in multicast DNAs or in link
local multicast name resolution. So we'll
filter those two out only 20 retransmitted
packets. Not bad, considering we stopped
the service on the primary DNA server. But
while it was down, our stub server answered a lot of the queries from cache