All logs will be found in below path:

<DCF-Install>/Collecting/Collector-Manager/<SP-Instance>(cloudify-orchestrator-collect)/logs/collecting-0-0.log

Latest processing log name will have "-0-0" appended to its name like above.

To enable logging, change the collecting configuration to push metrics/topology data to file connector like below. And after changing the configuration, operator need to restart the service to see the logging info in collecting-0-0.log.

Edit below file as specified below.

File : <DCF-Install>/Collecting/Collector-Manager/<SP-Instance>(cloudify-orchestrator-collect)/conf/collecting.xml
---
<connector enabled="true" name="File" type="File-Connector"   config="conf/file-connector.xml" />

---

Example: "cloudify-orchestrator-collect" is installed management pack name in below example.

To check the status of the installed services:
* Checking collector-manager cloudify-orchestrator-collect'...       [ running ]

To restart the specific service:

<DCF-Install>/bin/manage-modules.sh service restart collector-manager cloudify-orchestrator-collect
 * Stopping collector-manager cloudify-orchestrator-collect'...            [ OK ]
 * Starting collector-manager cloudify-orchestrator-collect '...            [ OK ]
Sample output (JSON) of metrics data in Kafka:
{	
 "groupName":"group",
 "discoveryID":null,
 "jobID":"9999",
 "type":"XMLDocumentManagementServer",
 "timestamp":1552452870,
 "value":0.0,
 "action":"r",
 "properties":{
    "context-name":"10.234.62.8",
	"networkName":"Private-Network",
	"hostId":"homer_host_xcyh8x",
	"source":"cloudify-orchestrator0b66e802-c13f-4df1-82b8-a2606fd059d4",
	"type":"XMLDocumentManagementServer",
	"Certification":"CERTIFIED",
	"cloudifyAgentIPAddress":"172.16.1.9",
	"Name":"homer_host_xcyh8x",
	"tenantName":"default_tenant",
	"Version":"4.5.0",
	"State":"started",
	"deploymentId":"Deployment",
	"DisplayName":"XDMS [172.16.1.11]",
	"ClassName":"XMLDocumentManagementServer",
	"networkId":"9d3569f0-1dc0-4a47-9135-3d2d63af3527",
	"id":"homer_host_xcyh8x",
	"IPAddress":"172.16.1.11",
	"nodeId":"homer_host"
},
 "metrics":{
	"CLOUDIFY-NODES-10.234.62.8":{
		"properties":{
		"unit":"code",
		"name":"CLOUDIFY-NODES-10.234.62.8"
		},
	"value":0.0
	}
 },
 "relations":[
 {
	"type":"XMLDocumentManagementServersGroup",
	"element":"homer_host_xcyh8x-172.16.1.11",
	"relationName":"PartOf"
 }
 ],
"initialized":true,
"forceRefresh":true,
"name":"homer_host_xcyh8x-172.16.1.11"
} 
Sample debugging (File Connector) output from collecting-0-0.log
INFO     -- [2019-04-11 01:01:36 EDT] -- CollectorManagerImpl::configure(): Parsing file '/opt/DCF/Collecting/Collector-Manager/cloudify-orchestrator-collect/conf/collecting.xml' ...
INFO     -- [2019-04-11 01:01:39 EDT] -- CollectorManagerImpl::getComponentInstance(): Instantiating class com.watch4net.apg.v2.collector.plugins.FileConnector for connector File...
INFO     -- [2019-04-11 01:01:39 EDT] -- CollectorManagerImpl::getComponentInstance(): Configuring connector File (FileConnector v1.0 rM) with /opt/DCF/Collecting/Collector-Manager/cloudify-orchestrator-collect/conf/file-connector.xml...
INFO     -- [2019-04-11 01:01:39 EDT] -- CollectorManagerImpl::configureConnectors(): Skipping disabled connector Kafka.
INFO     -- [2019-04-11 01:01:39 EDT] -- CollectorManagerImpl::getComponentInstance(): Instantiating class com.watch4net.apg.ubertext.collector.StreamCollector for collector CloudifyDiscovery...
INFO     -- [2019-04-11 01:01:39 EDT] -- CollectorManagerImpl::getComponentInstance(): Configuring collector CloudifyDiscovery (StreamCollector v1.4u2 rM) with /opt/DCF/Collecting/Stream-Collector/cloudify-orchestrator-collect/conf/discovery-cloudify.xml...
INFO     -- [2019-04-11 01:01:45 EDT] -- CollectorManagerImpl::connect(): Connecting collectors...
INFO     -- [2019-04-11 01:01:45 EDT] -- AbstractCollector::registerNext(): Connecting CloudifyDiscovery to File...
INFO     -- [2019-04-11 01:01:45 EDT] -- CollectorManagerImpl::configure(): endPacketSendlatch created with count :1
INFO     -- [2019-04-11 01:01:45 EDT] -- CollectorManagerImpl::configure(): Starting CollectionEndMsgTask thread...
INFO     -- [2019-04-11 01:01:45 EDT] -- CollectorManagerImpl::start(): Starting Collector Manager v5.10u1...
INFO     -- [2019-04-11 01:01:45 EDT] -- CollectorManagerImpl::start(): Initializing components...