tests/system-traffic: Ensure no name resolution for tcpdump.

Depending on system configuration, executing tcpdump without the
-n parameter, may prolong the execution time for tcpdump while it
attempts name resolution.

This delay may in turn lead to test failures due to contents of
tables to check being evicted.

We recently started to see this problem with the
"conntrack -IPv6 ICMP6 Related with SNAT" test.

For consistency, this patch adds the -n parameter to all tcpdump
calls in system-traffic.at.

Acked-by: Simon Horman <[email protected]>
Signed-off-by: Frode Nordahl <[email protected]>
Signed-off-by: Ilya Maximets <[email protected]>

tests/system-traffic.at

@@ -854,7 +854,7 @@ NS_CHECK_EXEC([at_ns0], [ping6 -q -c 3 -i 0.3 -w 2 fc00::100 | FORMAT_PING], [0]
 ])
 
 dnl Start tcpdump to capture the encapsulated packets.
-NETNS_DAEMONIZE([at_ns0], [tcpdump -U -i p0 -w p0.pcap], [tcpdump.pid])
+NETNS_DAEMONIZE([at_ns0], [tcpdump -n -U -i p0 -w p0.pcap], [tcpdump.pid])
 sleep 1
 
 dnl Generate a single packet trough the controler that needs an ARP modification
@@ -5625,7 +5625,7 @@ table=10 priority=0 action=drop
 AT_CHECK([ovs-ofctl --bundle add-flows br0 flows.txt])
 
 rm p0.pcap
-tcpdump -U -i ovs-p0 -w p0.pcap &
+tcpdump -n -U -i ovs-p0 -w p0.pcap &
 sleep 1
 
 dnl UDP packets from ns0->ns1 should solicit "destination unreachable" response.
@@ -5649,7 +5649,7 @@ AT_CHECK([ovs-appctl dpctl/dump-conntrack | FORMAT_CT(10.1.1.2) | sed -e 's/dst=
 udp,orig=(src=10.1.1.1,dst=10.1.1.2,sport=<cleared>,dport=<cleared>),reply=(src=10.1.1.2,dst=10.1.1.2XX,sport=<cleared>,dport=<cleared>),mark=1
 ])
 
-AT_CHECK([tcpdump -v "icmp" -r p0.pcap 2>/dev/null | grep -E 'wrong|bad'], [1], [ignore-nolog])
+AT_CHECK([tcpdump -n -v "icmp" -r p0.pcap 2>/dev/null | grep -E 'wrong|bad'], [1], [ignore-nolog])
 
 OVS_TRAFFIC_VSWITCHD_STOP
 AT_CLEANUP
@@ -6393,13 +6393,13 @@ OVS_WAIT_UNTIL([ip netns exec at_ns0 ping6 -c 1 fc00::2])
 AT_CHECK([ovs-appctl dpctl/flush-conntrack])
 
 rm p0.pcap
-tcpdump -U -i ovs-p0 -w p0.pcap &
+tcpdump -n -U -i ovs-p0 -w p0.pcap &
 sleep 1
 
 dnl UDP packets from ns0->ns1 should solicit "destination unreachable" response.
 NS_CHECK_EXEC([at_ns0], [bash -c "echo a | nc -6 $NC_EOF_OPT -u fc00::2 1"])
 
-AT_CHECK([tcpdump -v "icmp6" -r p0.pcap 2>/dev/null | grep -E 'wrong|bad'], [1], [ignore-nolog])
+AT_CHECK([tcpdump -n -v "icmp6" -r p0.pcap 2>/dev/null | grep -E 'wrong|bad'], [1], [ignore-nolog])
 
 AT_CHECK([ovs-appctl dpctl/dump-conntrack | FORMAT_CT(fc00::2)], [0], [dnl
 udp,orig=(src=fc00::1,dst=fc00::2,sport=<cleared>,dport=<cleared>),reply=(src=fc00::2,dst=fc00::240,sport=<cleared>,dport=<cleared>)
@@ -7161,7 +7161,7 @@ table=2,in_port=ovs-server,ip,ct_state=+trk+rpl,actions=output:ovs-client
 AT_CHECK([ovs-ofctl add-flows br0 flows.txt])
 
 rm server.pcap
-NETNS_DAEMONIZE([server], [tcpdump -l -U -i server -w server.pcap 2>tcpdump0_err], [tcpdump0.pid])
+NETNS_DAEMONIZE([server], [tcpdump -n -l -U -i server -w server.pcap 2>tcpdump0_err], [tcpdump0.pid])
 OVS_WAIT_UNTIL([grep "listening" tcpdump0_err])
 
 dnl Send UDP client->server
@@ -7203,7 +7203,7 @@ dnl Check the ICMP error in reply direction
 AT_CHECK([ovs-appctl dpctl/flush-conntrack zone=42])
 
 rm client.pcap
-NETNS_DAEMONIZE([client], [tcpdump -l -U -i client -w client.pcap 2>tcpdump1_err], [tcpdump1.pid])
+NETNS_DAEMONIZE([client], [tcpdump -n -l -U -i client -w client.pcap 2>tcpdump1_err], [tcpdump1.pid])
 OVS_WAIT_UNTIL([grep "listening" tcpdump1_err])
 
 dnl Send UDP client->server