All Event processing logs will be found in below path. This will have event spy logging info also, if enabled.

<DCF-Install>/Collecting/Collector-Manager/<INSTANCE>(ex:clearwater)/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/<INSTANCE>(clearwater)/conf/collecting.xml

---
<connector enabled="true" name="File" type="File-Connector"   config="conf/file-connector.xml" />

---
To check the status of the installed services:
<DCF-Install>/bin/manage-modules.sh service status all
* Checking 'collector-manager clearwater'...                        [ running ]

To restart the particular service:

<DCF-Install>/bin/manage-modules.sh service restart collector-manager clearwater
* Stopping 'collector-manager clearwater'...                             [ OK ]
 * Starting 'collector-manager clearwater'...                             [ OK ]
Sample JSON output:
{"groupName":"group","discoveryID":null,"jobID":"9999","type":"Sprout","timestamp":1554880287,"value":0.0,"action":"r","properties":{"oidIndex":"1","ip":"10.106.230.99","part":"scopePrevious5SecondPeriod","source":"SNMP-CLEARWATER","type":"Sprout","pollgrp":"PG_CLEARWATER-SPROUT","devdesc":"Linux cw-aio 3.16.0-30-generic #40~14.04.1-Ubuntu SMP Thu Jan 15 17:43:14 UTC 2015 x86_64","devtype":"vIMS","orchestrator":"default","vendor":"Clearwater","deploymentid":"default","location":"","model":"","table":"ICSCFSessionEstablishmentNetworkTable","datagrp":"PM"},"metrics":{"ICSCFSessionEstablishmentNetworkSuccesses":{"properties":{"unit":"integer","name":"ICSCFSessionEstablishmentNetworkSuccesses"},"value":0.0},"ICSCFSessionEstablishmentNetworkAttempts":{"properties":{"unit":"integer","name":"ICSCFSessionEstablishmentNetworkAttempts"},"value":0.0},"ICSCFSessionEstablishmentNetworkFailures":{"properties":{"unit":"integer","name":"ICSCFSessionEstablishmentNetworkFailures"},"value":0.0},"ICSCFSessionEstablishmentNetworkSuccessPercent":{"properties":{"unit":"integer","name":"ICSCFSessionEstablishmentNetworkSuccessPercent"},"value":1000000.0}},"relations":[],"initialized":true,"forceRefresh":true,"name":"10.106.230.99.ICSCFSessionEstablishmentNetworkTable.scopePrevious5SecondPeriod"}

Sample debugging (File Connector) output from collecting-0-0.log

INFO     -- [2019-04-10 03:11:24 EDT] -- CollectorManagerImpl::configure(): Parsing file '/opt/DCF/Collecting/Collector-Manager/clearwater/conf/collecting.xml' ...
INFO     -- [2019-04-10 03:11:25 EDT] -- CollectorManagerImpl::getComponentInstance(): Instantiating class com.watch4net.apg.v2.collector.plugins.FileConnector for connector File...
INFO     -- [2019-04-10 03:11:25 EDT] -- CollectorManagerImpl::getComponentInstance(): Configuring connector File (FileConnector v1.0 rM) with /opt/DCF/Collecting/Collector-Manager/clearwater/conf/file-connector.xml...
INFO     -- [2019-04-10 03:11:25 EDT] -- CollectorManagerImpl::getComponentInstance(): Instantiating class com.watch4net.apg.v2.collector.plugins.snmpCollector.SnmpCollectorSlave for collector CLEARWATER-SNMP...
INFO     -- [2019-04-10 03:11:25 EDT] -- W4nHeavySnmpSession::<clinit>(): SnmpOidSessionTTL value set to (ms): 600000
INFO     -- [2019-04-10 03:11:25 EDT] -- SnmpCollectorSlave::<clinit>(): Single oid polling session time to live set to 600,000 ms.
INFO     -- [2019-04-10 03:11:25 EDT] -- SnmpCollectorSlave::<clinit>(): Table polling session time to live set to 1,200,000 ms.
INFO     -- [2019-04-10 03:11:25 EDT] -- CollectorManagerImpl::getComponentInstance(): Configuring collector CLEARWATER-SNMP (SnmpCollectorSlave v6.8u2 rM) with /opt/DCF/Collecting/SNMP-Collector/clearwater/conf/snmpcollector.xml...
INFO     -- [2019-04-10 03:11:25 EDT] -- SnmpCollectorSlave::configureLogLevel(): SNMP packet decoding logging set to FATAL
INFO     -- [2019-04-10 03:11:25 EDT] -- CollectorManagerImpl::connect(): Connecting collectors...
INFO     -- [2019-04-10 03:11:25 EDT] -- AbstractCollector::registerNext(): Connecting CLEARWATER-SNMP to Param-CLEANUP...
INFO     -- [2019-04-10 03:11:25 EDT] -- CollectorManagerImpl::start(): Starting Collector Manager v5.10u1...