[#ZBX-25530] agent2 refuses to start randomly on windows

Example of agent startup and manual termination when everything is fine (DebugLevel=5):

2024/11/11 11:00:02.325179 Starting Zabbix Agent 2 (7.0.5)
2024/11/11 11:00:02.326283 Calling C function "tls_new_context()"
2024/11/11 11:00:02.327482 Calling C function "tls_new_context()"
2024/11/11 11:00:02.327570 Calling C function "tls_version()"
2024/11/11 11:00:02.327570 OpenSSL library (OpenSSL 3.0.11 19 Sep 2023) initialized
2024/11/11 11:00:02.328110 Calling C function "tls_describe_ciphersuites()"
2024/11/11 11:00:02.328110 Calling C function "free()"
2024/11/11 11:00:02.328110 default context ciphersuites: TLS_CHACHA20_POLY1305_SHA256 TLS_AES_128_GCM_SHA256 ECDHE-PSK-AES128-CBC-SHA256 ECDHE-PSK-AES128-CBC-SHA PSK-AES128-GCM-SHA256 PSK-AES128-CCM8 PSK-AES128-CCM PSK-AES128-CBC-SHA256 PSK-AES128-CBC-SHA
2024/11/11 11:00:02.328110 Calling C function "tls_describe_ciphersuites()"
2024/11/11 11:00:02.328344 Calling C function "free()"
2024/11/11 11:00:02.328344 psk context ciphersuites: TLS_CHACHA20_POLY1305_SHA256 TLS_AES_128_GCM_SHA256 ECDHE-PSK-AES128-CBC-SHA256 ECDHE-PSK-AES128-CBC-SHA PSK-AES128-GCM-SHA256 PSK-AES128-CCM8 PSK-AES128-CCM PSK-AES128-CBC-SHA256 PSK-AES128-CBC-SHA
2024/11/11 11:00:02.328344 using configuration file: C:\zabbix\config\zabbix_agent2.conf
2024/11/11 11:00:02.328618 using plugin 'Agent' (built-in) providing following interfaces: exporter
2024/11/11 11:00:02.328618 using plugin 'Ceph' (built-in) providing following interfaces: exporter, runner, configurator
2024/11/11 11:00:02.328618 using plugin 'Cpu' (built-in) providing following interfaces: exporter, collector, runner
2024/11/11 11:00:02.328618 using plugin 'DNS' (built-in) providing following interfaces: exporter
2024/11/11 11:00:02.328618 using plugin 'File' (built-in) providing following interfaces: exporter, configurator
2024/11/11 11:00:02.328618 using plugin 'Log' (built-in) providing following interfaces: exporter, configurator
2024/11/11 11:00:02.328618 using plugin 'MQTT' (built-in) providing following interfaces: watcher, configurator
2024/11/11 11:00:02.328618 using plugin 'Memcached' (built-in) providing following interfaces: exporter, runner, configurator
2024/11/11 11:00:02.328618 using plugin 'Memory' (built-in) providing following interfaces: exporter
2024/11/11 11:00:02.329154 using plugin 'Modbus' (built-in) providing following interfaces: exporter, configurator
2024/11/11 11:00:02.329210 using plugin 'Mysql' (built-in) providing following interfaces: exporter, runner, configurator
2024/11/11 11:00:02.329210 using plugin 'NetIf' (built-in) providing following interfaces: exporter
2024/11/11 11:00:02.329210 using plugin 'Oracle' (built-in) providing following interfaces: exporter, runner, configurator
2024/11/11 11:00:02.329210 using plugin 'Proc' (built-in) providing following interfaces: exporter
2024/11/11 11:00:02.329210 using plugin 'Redis' (built-in) providing following interfaces: exporter, runner, configurator
2024/11/11 11:00:02.329210 using plugin 'Registry' (built-in) providing following interfaces: exporter
2024/11/11 11:00:02.329210 using plugin 'Smart' (built-in) providing following interfaces: exporter, configurator
2024/11/11 11:00:02.329210 using plugin 'Sw' (built-in) providing following interfaces: exporter, configurator
2024/11/11 11:00:02.329210 using plugin 'Swap' (built-in) providing following interfaces: exporter
2024/11/11 11:00:02.329736 using plugin 'SystemRun' (built-in) providing following interfaces: exporter, configurator
2024/11/11 11:00:02.329768 using plugin 'TCP' (built-in) providing following interfaces: exporter, configurator
2024/11/11 11:00:02.329833 using plugin 'UDP' (built-in) providing following interfaces: exporter, configurator
2024/11/11 11:00:02.329833 using plugin 'Uname' (built-in) providing following interfaces: exporter
2024/11/11 11:00:02.329833 using plugin 'Uptime' (built-in) providing following interfaces: exporter
2024/11/11 11:00:02.329833 using plugin 'UserParameter' (built-in) providing following interfaces: exporter
2024/11/11 11:00:02.329833 using plugin 'Users' (built-in) providing following interfaces: exporter, configurator
2024/11/11 11:00:02.329833 using plugin 'VFSDir' (built-in) providing following interfaces: exporter
2024/11/11 11:00:02.329833 using plugin 'VMemory' (built-in) providing following interfaces: exporter
2024/11/11 11:00:02.329833 using plugin 'VfsFs' (built-in) providing following interfaces: exporter
2024/11/11 11:00:02.329833 using plugin 'WebCertificate' (built-in) providing following interfaces: exporter, configurator
2024/11/11 11:00:02.329833 using plugin 'WebPage' (built-in) providing following interfaces: exporter, configurator
2024/11/11 11:00:02.329833 using plugin 'WindowsEventlog' (built-in) providing following interfaces: exporter, configurator
2024/11/11 11:00:02.330412 lowering the plugin WindowsPerfInstance capacity to 1 as the configured capacity 1000 exceeds limits
2024/11/11 11:00:02.330412 using plugin 'WindowsPerfInstance' (built-in) providing following interfaces: exporter
2024/11/11 11:00:02.330412 using plugin 'WindowsPerfMon' (built-in) providing following interfaces: exporter, collector, runner
2024/11/11 11:00:02.330412 using plugin 'WindowsServices' (built-in) providing following interfaces: exporter
2024/11/11 11:00:02.330412 using plugin 'Wmi' (built-in) providing following interfaces: exporter
2024/11/11 11:00:02.330624 using plugin 'ZabbixAsync' (built-in) providing following interfaces: exporter
2024/11/11 11:00:02.330624 using plugin 'ZabbixStats' (built-in) providing following interfaces: exporter, configurator
2024/11/11 11:00:02.330624 lowering the plugin ZabbixSync capacity to 1 as the configured capacity 1000 exceeds limits
2024/11/11 11:00:02.330624 using plugin 'ZabbixSync' (built-in) providing following interfaces: exporter
2024/11/11 11:00:02.330624 [Modbus] Config is valid
2024/11/11 11:00:03.059654 Plugin communication protocol version is 6.4.0
2024/11/11 11:00:03.060177 Zabbix Agent2 hostname: [xxx]
...
2024/11/11 11:00:05.407524 listener has been stopped
2024/11/11 11:00:05.407640 [101] server connector has been stopped
2024/11/11 11:00:05.407748 manager has been stopped
2024/11/11 11:00:05.407837 [101] memory cache has been stopped
2024/11/11 11:00:05.407941 Zabbix Agent 2 stopped. (7.0.5)

After 10 seconds attempt to start it again and it fails, complete log:

2024/11/11 11:00:16.176147 Starting Zabbix Agent 2 (7.0.5)
2024/11/11 11:00:16.176745 Calling C function "tls_new_context()"
2024/11/11 11:00:16.177898 Calling C function "tls_new_context()"
2024/11/11 11:00:16.178601 Calling C function "tls_version()"
2024/11/11 11:00:16.178601 OpenSSL library (OpenSSL 3.0.11 19 Sep 2023) initialized
2024/11/11 11:00:16.178601 Calling C function "tls_describe_ciphersuites()"
2024/11/11 11:00:16.178601 Calling C function "free()"
2024/11/11 11:00:16.178601 default context ciphersuites: TLS_CHACHA20_POLY1305_SHA256 TLS_AES_128_GCM_SHA256 ECDHE-PSK-AES128-CBC-SHA256 ECDHE-PSK-AES128-CBC-SHA PSK-AES128-GCM-SHA256 PSK-AES128-CCM8 PSK-AES128-CCM PSK-AES128-CBC-SHA256 PSK-AES128-CBC-SHA
2024/11/11 11:00:16.178601 Calling C function "tls_describe_ciphersuites()"
2024/11/11 11:00:16.178601 Calling C function "free()"
2024/11/11 11:00:16.178601 psk context ciphersuites: TLS_CHACHA20_POLY1305_SHA256 TLS_AES_128_GCM_SHA256 ECDHE-PSK-AES128-CBC-SHA256 ECDHE-PSK-AES128-CBC-SHA PSK-AES128-GCM-SHA256 PSK-AES128-CCM8 PSK-AES128-CCM PSK-AES128-CBC-SHA256 PSK-AES128-CBC-SHA
2024/11/11 11:00:16.179135 using configuration file: C:\zabbix\config\zabbix_agent2.conf
2024/11/11 11:00:16.179198 using plugin 'Agent' (built-in) providing following interfaces: exporter
2024/11/11 11:00:16.179198 using plugin 'Ceph' (built-in) providing following interfaces: exporter, runner, configurator
2024/11/11 11:00:16.179198 using plugin 'Cpu' (built-in) providing following interfaces: exporter, collector, runner
2024/11/11 11:00:16.179198 using plugin 'DNS' (built-in) providing following interfaces: exporter
2024/11/11 11:00:16.179198 using plugin 'File' (built-in) providing following interfaces: exporter, configurator
2024/11/11 11:00:16.179198 using plugin 'Log' (built-in) providing following interfaces: exporter, configurator
2024/11/11 11:00:16.179198 using plugin 'MQTT' (built-in) providing following interfaces: watcher, configurator
2024/11/11 11:00:16.179772 using plugin 'Memcached' (built-in) providing following interfaces: exporter, runner, configurator
2024/11/11 11:00:16.179788 using plugin 'Memory' (built-in) providing following interfaces: exporter
2024/11/11 11:00:16.179788 using plugin 'Modbus' (built-in) providing following interfaces: exporter, configurator
2024/11/11 11:00:16.179788 using plugin 'Mysql' (built-in) providing following interfaces: exporter, runner, configurator
2024/11/11 11:00:16.179788 using plugin 'NetIf' (built-in) providing following interfaces: exporter
2024/11/11 11:00:16.179788 using plugin 'Oracle' (built-in) providing following interfaces: exporter, runner, configurator
2024/11/11 11:00:16.179788 using plugin 'Proc' (built-in) providing following interfaces: exporter
2024/11/11 11:00:16.179788 using plugin 'Redis' (built-in) providing following interfaces: exporter, runner, configurator
2024/11/11 11:00:16.179788 using plugin 'Registry' (built-in) providing following interfaces: exporter
2024/11/11 11:00:16.180322 using plugin 'Smart' (built-in) providing following interfaces: exporter, configurator
2024/11/11 11:00:16.180372 using plugin 'Sw' (built-in) providing following interfaces: exporter, configurator
2024/11/11 11:00:16.180393 using plugin 'Swap' (built-in) providing following interfaces: exporter
2024/11/11 11:00:16.180393 using plugin 'SystemRun' (built-in) providing following interfaces: exporter, configurator
2024/11/11 11:00:16.180393 using plugin 'TCP' (built-in) providing following interfaces: exporter, configurator
2024/11/11 11:00:16.180393 using plugin 'UDP' (built-in) providing following interfaces: exporter, configurator
2024/11/11 11:00:16.180393 using plugin 'Uname' (built-in) providing following interfaces: exporter
2024/11/11 11:00:16.180393 using plugin 'Uptime' (built-in) providing following interfaces: exporter
2024/11/11 11:00:16.180393 using plugin 'UserParameter' (built-in) providing following interfaces: exporter
2024/11/11 11:00:16.180393 using plugin 'Users' (built-in) providing following interfaces: exporter, configurator
2024/11/11 11:00:16.180393 using plugin 'VFSDir' (built-in) providing following interfaces: exporter
2024/11/11 11:00:16.180959 using plugin 'VMemory' (built-in) providing following interfaces: exporter
2024/11/11 11:00:16.180987 using plugin 'VfsFs' (built-in) providing following interfaces: exporter
2024/11/11 11:00:16.181055 using plugin 'WebCertificate' (built-in) providing following interfaces: exporter, configurator
2024/11/11 11:00:16.181055 using plugin 'WebPage' (built-in) providing following interfaces: exporter, configurator
2024/11/11 11:00:16.181055 using plugin 'WindowsEventlog' (built-in) providing following interfaces: exporter, configurator
2024/11/11 11:00:16.181055 lowering the plugin WindowsPerfInstance capacity to 1 as the configured capacity 1000 exceeds limits
2024/11/11 11:00:16.181055 using plugin 'WindowsPerfInstance' (built-in) providing following interfaces: exporter
2024/11/11 11:00:16.181055 using plugin 'WindowsPerfMon' (built-in) providing following interfaces: exporter, collector, runner
2024/11/11 11:00:16.181055 using plugin 'WindowsServices' (built-in) providing following interfaces: exporter
2024/11/11 11:00:16.181055 using plugin 'Wmi' (built-in) providing following interfaces: exporter
2024/11/11 11:00:16.181055 using plugin 'ZabbixAsync' (built-in) providing following interfaces: exporter
2024/11/11 11:00:16.181055 using plugin 'ZabbixStats' (built-in) providing following interfaces: exporter, configurator
2024/11/11 11:00:16.181055 lowering the plugin ZabbixSync capacity to 1 as the configured capacity 1000 exceeds limits
2024/11/11 11:00:16.181599 using plugin 'ZabbixSync' (built-in) providing following interfaces: exporter
2024/11/11 11:00:16.181665 [Modbus] Config is valid
2024/11/11 11:00:17.011124 Cannot load os dependent items: failed to load objects and default counters:      There is more data to return than will fit in the supplied buffer. Allocate a larger buffer and call the function again.

We saw that message from Windows running using other locales, then the last line looks this way, Japanese locale:

2024/10/29 11:48:14.620762 Zabbix Agent 2 stopped. (6.0.35)
2024/10/29 11:48:15.989490 Starting Zabbix Agent 2 (6.0.35)
...
2024/10/29 11:48:17.560835 cannot load os dependent items: Failed to load objects and default counters: 与えられたバッファーが小さすぎます。より大きいバッファーを割り当てて、もう一度関数を呼び出してください。.

It's unclear why this issue is happening, this should be addressed.

[ZBX-25530] agent2 refuses to start randomly on windows - "Cannot load os dependent items" Created: 2024 Nov 11 Updated: 2025 Mar 25 Resolved: 2025 Feb 07
Status:	Closed
Project:	ZABBIX BUGS AND ISSUES
Component/s:	Agent (G)
Affects Version/s:	6.0.34, 7.0.5
Fix Version/s:	6.0.39rc1, 7.0.10rc1, 7.2.4rc1, 7.4.0alpha1

[ZBX-25530] agent2 refuses to start randomly on windows - "Cannot load os dependent items" Created: 2024 Nov 11 Updated: 2025 Mar 25 Resolved: 2025 Feb 07