Don't count pings while a guest OS is booting

This test is sending ICMP pings to microVMs.

However since Machine#Start() only *starts* a microVM and not aware
about the status of the guest OS, some packets are sent while the OS is
booting, which would be the cause of the flakiness of the test.

Signed-off-by: Kazuyoshi Kato <[email protected]>

Author: kzys

network_test.go

@@ -453,12 +453,23 @@ func startCNIMachine(t *testing.T, ctx context.Context, m *Machine) string {
 }
 
 func testPing(t *testing.T, ip string, count int, timeout time.Duration) {
+	// First, send one ping to make sure the machine is up
 	pinger, err := ping.NewPinger(ip)
 	require.NoError(t, err, "failed to create pinger")
+	pinger.SetPrivileged(true)
+
+	pinger.Count = 1
+	pinger.Timeout = 5 * time.Second
+	pinger.Run()
+
+	// Then send multiple pings to check that the network is working correctly
+	pinger, err = ping.NewPinger(ip)
+	require.NoError(t, err, "failed to create pinger")
+	pinger.SetPrivileged(true)
 	pinger.Count = count
 	pinger.Timeout = timeout
-	pinger.SetPrivileged(true)
 	pinger.Run()
+
 	pingStats := pinger.Statistics()
 	assert.Equal(t, pinger.Count, pingStats.PacketsRecv, "machine did not respond to all pings")
 }