**CMK version:*2.1.0p40.cee *
**OS version:*Red Hat Enterprise Linux release 8.9 *
**Error message:ConnectionResetError(104, ‘Connection reset by peer’)
Output of “cmk --debug -vvn hostname”:
OMD[pdc1]:~$ cmk --debug -vvn dinoaccapp22
Checkmk version 2.1.0p40
Try license usage history update.
Trying to acquire lock on /omd/sites/pdc1/var/check_mk/license_usage/next_run
Got lock on /omd/sites/pdc1/var/check_mk/license_usage/next_run
Trying to acquire lock on /omd/sites/pdc1/var/check_mk/license_usage/history.json
Got lock on /omd/sites/pdc1/var/check_mk/license_usage/history.json
Next run time has not been reached yet. Abort.
Releasing lock on /omd/sites/pdc1/var/check_mk/license_usage/history.json
Released lock on /omd/sites/pdc1/var/check_mk/license_usage/history.json
Releasing lock on /omd/sites/pdc1/var/check_mk/license_usage/next_run
Released lock on /omd/sites/pdc1/var/check_mk/license_usage/next_run
+ FETCHING DATA
Source: SourceType.HOST/FetcherType.TCP
[cpu_tracking] Start [7fe245ded130]
[TCPFetcher] Fetch with cache settings: DefaultAgentFileCache(dinoaccapp22, base_path=/omd/sites/pdc1/tmp/check_mk/cache, max_age=MaxAge(checking=0, discovery=540, inventory=540), disabled=False, use_outdated=False, simulation=False)
Not using cache (Does not exist)
[TCPFetcher] Execute data source
Connecting via TCP to 10.XX.XX.XX:6556 (180.0s timeout)
Detected transport protocol: TransportProtocol.TLS (b'16')
Reading data from agent via TLS socket
Closing TCP connection to 10.XX.XX.XX:6556
[cpu_tracking] Stop [7fe245ded130 - Snapshot(process=posix.times_result(user=0.0, system=0.0, children_user=0.0, children_system=0.0, elapsed=0.009999999776482582))]
Source: SourceType.HOST/FetcherType.PIGGYBACK
[cpu_tracking] Start [7fe245ded9a0]
[PiggybackFetcher] Fetch with cache settings: NoCache(dinoaccapp22, base_path=/omd/sites/pdc1/tmp/check_mk/data_source_cache/piggyback, max_age=MaxAge(checking=0, discovery=540, inventory=540), disabled=True, use_outdated=False, simulation=False)
Not using cache (Cache usage disabled)
[PiggybackFetcher] Execute data source
No piggyback files for 'dinoaccapp22'. Skip processing.
No piggyback files for '10.XX.XX.XX'. Skip processing.
Not using cache (Cache usage disabled)
[cpu_tracking] Stop [7fe245ded9a0 - Snapshot(process=posix.times_result(user=0.0, system=0.0, children_user=0.0, children_system=0.0, elapsed=0.0))]
+ PARSE FETCHER RESULTS
Source: SourceType.HOST/FetcherType.TCP
-> Not adding sections: ConnectionResetError(104, 'Connection reset by peer')
Source: SourceType.HOST/FetcherType.PIGGYBACK
No persisted sections
-> Add sections: []
Received no piggyback data
Received no piggyback data
[cpu_tracking] Start [7fe245deda90]
value store: synchronizing
Trying to acquire lock on /omd/sites/pdc1/tmp/check_mk/counters/dinoaccapp22
Got lock on /omd/sites/pdc1/tmp/check_mk/counters/dinoaccapp22
value store: loading from disk
Releasing lock on /omd/sites/pdc1/tmp/check_mk/counters/dinoaccapp22
Released lock on /omd/sites/pdc1/tmp/check_mk/counters/dinoaccapp22
Log Forwarding PEND - Check plugin received no monitoring data
proc_puppet PEND - Check plugin received no monitoring data
proc_runpup PEND - Check plugin received no monitoring data
No piggyback files for 'dinoaccapp22'. Skip processing.
No piggyback files for '10.XX.XX.XX'. Skip processing.
[cpu_tracking] Stop [7fe245deda90 - Snapshot(process=posix.times_result(user=0.0, system=0.0, children_user=0.0, children_system=0.0, elapsed=0.0))]
[agent] ConnectionResetError(104, 'Connection reset by peer')(!!), Got no information from host(!!), execution time 0.0 sec | execution_time=0.010 user_time=0.000 system_time=0.000 children_user_time=0.000 children_system_time=0.000 cmk_time_agent=0.010
* (If it is a problem with checks or plugins)