func (s *syslogSuite) SetUpTest(c *gc.C) {
	if runtime.GOOS != "linux" {
		c.Skip(fmt.Sprintf("this test requires a controller, therefore does not support %q", runtime.GOOS))
	}
	currentSeries := series.HostSeries()
	osFromSeries, err := series.GetOSFromSeries(currentSeries)
	c.Assert(err, jc.ErrorIsNil)
	if osFromSeries != os.Ubuntu {
		c.Skip(fmt.Sprintf("this test requires a controller, therefore does not support OS %q only Ubuntu", osFromSeries.String()))
	}
	s.AgentSuite.SetUpTest(c)
	// TODO(perrito666) 200160701:
	// This needs to be done to stop the test from trying to install mongo
	// while running, but it is a huge footprint for such little benefit.
	// This test should not need JujuConnSuite or AgentSuite.
	s.fakeEnsureMongo = agenttest.InstallFakeEnsureMongo(s)

	done := make(chan struct{})
	s.received = make(chan rfc5424test.Message)
	addr := s.createSyslogServer(c, s.received, done)

	// Leave log forwarding disabled initially, it will be enabled
	// via a model config update in the test.
	err = s.State.UpdateModelConfig(map[string]interface{}{
		"syslog-host":        addr,
		"syslog-ca-cert":     coretesting.CACert,
		"syslog-client-cert": coretesting.ServerCert,
		"syslog-client-key":  coretesting.ServerKey,
	}, nil, nil)
	c.Assert(err, jc.ErrorIsNil)

	s.logsCh, err = logsender.InstallBufferedLogWriter(1000)
	c.Assert(err, jc.ErrorIsNil)
}

// Main registers subcommands for the jujud executable, and hands over control
// to the cmd package.
func jujuDMain(args []string, ctx *cmd.Context) (code int, err error) {
	// Assuming an average of 200 bytes per log message, use up to
	// 200MB for the log buffer.
	logCh, err := logsender.InstallBufferedLogWriter(1048576)
	if err != nil {
		return 1, errors.Trace(err)
	}

	jujud := jujucmd.NewSuperCommand(cmd.SuperCommandParams{
		Name: "jujud",
		Doc:  jujudDoc,
	})
	jujud.Log.Factory = &writerFactory{}
	jujud.Register(NewBootstrapCommand())

	// TODO(katco-): AgentConf type is doing too much. The
	// MachineAgent type has called out the separate concerns; the
	// AgentConf should be split up to follow suit.
	agentConf := agentcmd.NewAgentConf("")
	machineAgentFactory := agentcmd.MachineAgentFactoryFn(
		agentConf, logCh, looputil.NewLoopDeviceManager(),
	)
	jujud.Register(agentcmd.NewMachineAgentCmd(ctx, machineAgentFactory, agentConf, agentConf))

	jujud.Register(agentcmd.NewUnitAgent(ctx, logCh))

	code = cmd.Main(jujud, ctx, args[1:])
	return code, nil
}

func (s *dblogSuite) runUnitAgentTest(c *gc.C) bool {
	// Lease setup stuff, only needed when running a uniter.
	m, err := lease.NewLeaseManager(s.State)
	c.Assert(err, jc.ErrorIsNil)
	s.AddCleanup(func(c *gc.C) {
		m.Kill()
		c.Assert(m.Wait(), jc.ErrorIsNil)
	})
	// Create a unit and an agent for it.
	u, password := s.Factory.MakeUnitReturningPassword(c, nil)
	s.PrimeAgent(c, u.Tag(), password, version.Current)
	logsCh, err := logsender.InstallBufferedLogWriter(1000)
	c.Assert(err, jc.ErrorIsNil)
	a := agentcmd.NewUnitAgent(nil, logsCh)
	s.InitAgent(c, a, "--unit-name", u.Name(), "--log-to-stderr=true")

	// Ensure there's no logs to begin with.
	c.Assert(s.getLogCount(c, u.Tag()), gc.Equals, 0)

	// Start the agent.
	go func() { c.Assert(a.Run(nil), jc.ErrorIsNil) }()
	defer a.Stop()

	return s.waitForLogs(c, u.Tag())
}

// Main registers subcommands for the jujud executable, and hands over control
// to the cmd package.
func jujuDMain(args []string, ctx *cmd.Context) (code int, err error) {
	// Assuming an average of 200 bytes per log message, use up to
	// 200MB for the log buffer.
	defer logger.Debugf("jujud complete, code %d, err %v", code, err)
	logCh, err := logsender.InstallBufferedLogWriter(1048576)
	if err != nil {
		return 1, errors.Trace(err)
	}

	jujud := jujucmd.NewSuperCommand(cmd.SuperCommandParams{
		Name: "jujud",
		Doc:  jujudDoc,
	})

	jujud.Log.NewWriter = func(target io.Writer) loggo.Writer {
		return &jujudWriter{target: target}
	}

	jujud.Register(NewBootstrapCommand())

	// TODO(katco-): AgentConf type is doing too much. The
	// MachineAgent type has called out the separate concerns; the
	// AgentConf should be split up to follow suit.
	agentConf := agentcmd.NewAgentConf("")
	machineAgentFactory := agentcmd.MachineAgentFactoryFn(agentConf, logCh, "")
	jujud.Register(agentcmd.NewMachineAgentCmd(ctx, machineAgentFactory, agentConf, agentConf))

	jujud.Register(agentcmd.NewUnitAgent(ctx, logCh))

	jujud.Register(NewUpgradeMongoCommand())

	code = cmd.Main(jujud, ctx, args[1:])
	return code, nil
}

func (s *bufferedLogWriterSuite) TestUninstallBufferedLogWriter(c *gc.C) {
	_, err := logsender.InstallBufferedLogWriter(10)
	c.Assert(err, jc.ErrorIsNil)

	err = logsender.UninstallBufferedLogWriter()
	c.Assert(err, jc.ErrorIsNil)

	// Second uninstall attempt should fail
	err = logsender.UninstallBufferedLogWriter()
	c.Assert(err, gc.ErrorMatches, "failed to uninstall log buffering: .+")
}

func (s *dblogSuite) runUnitAgentTest(c *gc.C) bool {
	// Create a unit and an agent for it.
	u, password := s.Factory.MakeUnitReturningPassword(c, nil)
	s.PrimeAgent(c, u.Tag(), password)
	logsCh, err := logsender.InstallBufferedLogWriter(1000)
	c.Assert(err, jc.ErrorIsNil)
	a := agentcmd.NewUnitAgent(nil, logsCh)
	s.InitAgent(c, a, "--unit-name", u.Name(), "--log-to-stderr=true")

	// Ensure there's no logs to begin with.
	c.Assert(s.getLogCount(c, u.Tag()), gc.Equals, 0)

	// Start the agent.
	go func() { c.Assert(a.Run(nil), jc.ErrorIsNil) }()
	defer a.Stop()

	return s.waitForLogs(c, u.Tag())
}

func (s *bufferedLogWriterSuite) TestInstallBufferedLogWriter(c *gc.C) {
	logsCh, err := logsender.InstallBufferedLogWriter(10)
	c.Assert(err, jc.ErrorIsNil)
	defer logsender.UninstallBufferedLogWriter()

	logger := loggo.GetLogger("bufferedLogWriter-test")

	for i := 0; i < 5; i++ {
		logger.Infof("%d", i)
	}

	for i := 0; i < 5; i++ {
		select {
		case rec := <-logsCh:
			c.Assert(rec.Message, gc.Equals, strconv.Itoa(i))
		case <-time.After(coretesting.LongWait):
			c.Fatal("timed out waiting for logs")
		}
	}
}

func (s *dblogSuite) runMachineAgentTest(c *gc.C) bool {
	// Create a machine and an agent for it.
	m, password := s.Factory.MakeMachineReturningPassword(c, &factory.MachineParams{
		Nonce: agent.BootstrapNonce,
	})

	s.PrimeAgent(c, m.Tag(), password, version.Current)
	agentConf := agentcmd.NewAgentConf(s.DataDir())
	agentConf.ReadConfig(m.Tag().String())
	logsCh, err := logsender.InstallBufferedLogWriter(1000)
	c.Assert(err, jc.ErrorIsNil)
	machineAgentFactory := agentcmd.MachineAgentFactoryFn(agentConf, agentConf, logsCh, nil)
	a := machineAgentFactory(m.Id())

	// Ensure there's no logs to begin with.
	c.Assert(s.getLogCount(c, m.Tag()), gc.Equals, 0)

	// Start the agent.
	go func() { c.Check(a.Run(nil), jc.ErrorIsNil) }()
	defer a.Stop()

	return s.waitForLogs(c, m.Tag())
}

func (s *bufferedLogWriterSuite) TestInstallBufferedLogWriterNoFeatureFlag(c *gc.C) {
	logsCh, err := logsender.InstallBufferedLogWriter(10)
	c.Assert(err, jc.ErrorIsNil)
	c.Assert(logsCh, gc.IsNil)
}