3 Zabbix agent (UNIX)

Overview

This section lists parameters supported in a Zabbix agent configuration file (zabbix_agentd.conf). Note that:

  • The default values reflect daemon defaults, not the values in the shipped configuration files;
  • Zabbix supports configuration files only in UTF-8 encoding without BOM;
  • Comments starting with "#" are only supported in the beginning of the line.

Parameters

Parameter Mandatory Range Default Description
Alias no Sets an alias for an item key. It can be used to substitute long and complex item key with a smaller and simpler one.
Multiple Alias parameters may be present. Multiple parameters with the same Alias key are not allowed.
Different Alias keys may reference the same item key.
Aliases can be used in HostMetadataItem but not in HostnameItem parameters.

Examples:

1. Retrieving the ID of user 'zabbix'.
Alias=zabbix.userid:vfs.file.regexp[/etc/passwd,"^zabbix:.:([0-9]+)",,,,\1]
Now shorthand key zabbix.userid may be used to retrieve data.

2. Getting CPU utilization with default and custom parameters.
Alias=cpu.util:system.cpu.util
Alias=cpu.util[*]:system.cpu.util[*]
This allows use cpu.util key to get CPU utilization percentage with default parameters as well as use cpu.util[all, idle, avg15] to get specific data about CPU utilization.

3. Running multiple low-level discovery rules processing the same discovery items.
Alias=vfs.fs.discovery[*]:vfs.fs.discovery
Now it is possible to set up several discovery rules using vfs.fs.discovery with different parameters for each rule, e.g., vfs.fs.discovery[foo], vfs.fs.discovery[bar], etc.
AllowKey no Allow execution of those item keys that match a pattern. Key pattern is a wildcard expression that supports "*" character to match any number of any characters.
Multiple key matching rules may be defined in combination with DenyKey. The parameters are processed one by one according to their appearance order.
This parameter is supported since Zabbix 5.0.0.
See also: Restricting agent checks.
AllowRoot no 0 Allow the agent to run as 'root'. If disabled and the agent is started by 'root', the agent will try to switch to user 'zabbix' instead. Has no effect if started under a regular user.
0 - do not allow
1 - allow
BufferSend no 1-3600 5 Do not keep data longer than N seconds in buffer.
BufferSize no 2-65535 100 Maximum number of values in a memory buffer. The agent will send
all collected data to Zabbix server or proxy if the buffer is full.
DebugLevel no 0-5 3 Specifies debug level:
0 - basic information about starting and stopping of Zabbix processes
1 - critical information
2 - error information
3 - warnings
4 - for debugging (produces lots of information)
5 - extended debugging (produces even more information)
DenyKey no Deny execution of those item keys that match a pattern. Key pattern is a wildcard expression that supports "*" character to match any number of any characters.
Multiple key matching rules may be defined in combination with AllowKey. The parameters are processed one by one according to their appearance order.
This parameter is supported since Zabbix 5.0.0.
See also: Restricting agent checks.
EnableRemoteCommands no 0 Whether remote commands from Zabbix server are allowed. Since Zabbix 5.0.2, this parameter is deprecated, use AllowKey=system.run[*] or DenyKey=system.run[*] instead
It is internal alias for AllowKey/DenyKey parameters depending on value: 0 - DenyKey=system.run[*]
1 - AllowKey=system.run[*]
HostInterface no 0-255 characters Optional parameter that defines host interface.
Host interface is used at host autoregistration process.
An agent will issue an error and not start if the value is over the limit of 255 characters.
If not defined, value will be acquired from HostInterfaceItem.
Supported since Zabbix 4.4.0.
HostInterfaceItem no Optional parameter that defines an item used for getting host interface.
Host interface is used at host autoregistration process.
During an autoregistration request an agent will log a warning message if the value returned by specified item is over limit of 255 characters.
The system.run[] item is supported regardless of AllowKey/DenyKey values.
This option is only used when HostInterface is not defined.
Supported since Zabbix 4.4.0.
HostMetadata no 0-255 characters Optional parameter that defines host metadata. Host metadata is used only at host autoregistration process (active agent).
If not defined, the value will be acquired from HostMetadataItem.
An agent will issue an error and not start if the specified value is over the limit or a non-UTF-8 string.
This option is supported in version 2.2.0 and higher.
HostMetadataItem no Optional parameter that defines a Zabbix agent item used for getting host metadata. This option is only used when HostMetadata is not defined.
Supports UserParameters and aliases. Supports system.run[] regardless of AllowKey/DenyKey values.
HostMetadataItem value is retrieved on each autoregistration attempt and is used only at host autoregistration process (active agent).
During an autoregistration request an agent will log a warning message if the value returned by the specified item is over the limit of 255 characters.
The value returned by the item must be a UTF-8 string otherwise it will be ignored.
This option is supported in version 2.2.0 and higher.
Hostname no Set by HostnameItem Unique, case sensitive hostname.
Required for active checks and must match hostname as configured on the server.
Allowed characters: alphanumeric, '.', ' ', '_' and '-'.
Maximum length: 128
HostnameItem no system.hostname Optional parameter that defines a Zabbix agent item used for getting host name. This option is only used when Hostname is not defined.
Does not support UserParameters or aliases, but does support system.run[] regardless of AllowKey/DenyKey values.
This option is supported in version 1.8.6 and higher.
Include no You may include individual files or all files in a directory in the configuration file.
To only include relevant files in the specified directory, the asterisk wildcard character is supported for pattern matching. For example: /absolute/path/to/config/files/*.conf. Pattern matching is supported since Zabbix 2.4.0.
See special notes about limitations.
ListenBacklog no 0 - INT_MAX SOMAXCONN The maximum number of pending connections in the TCP queue.
Default value is a hard-coded constant, which depends on the system.
Maximum supported value depends on the system, too high values may be silently truncated to the 'implementation-specified maximum'.
ListenIP no 0.0.0.0 List of comma delimited IP addresses that the agent should listen on.
Multiple IP addresses are supported in version 1.8.3 and higher.
ListenPort no 1024-32767 10050 Agent will listen on this port for connections from the server.
LoadModule no Module to load at agent startup. Modules are used to extend functionality of the agent.
Formats:
LoadModule=<module.so>
LoadModule=<path/module.so>
LoadModule=</abs_path/module.so>
Either the module must be located in directory specified by LoadModulePath or the path must precede the module name. If the preceding path is absolute (starts with '/') then LoadModulePath is ignored.
It is allowed to include multiple LoadModule parameters.
LoadModulePath no Full path to location of agent modules.
Default depends on compilation options.
LogFile yes, if LogType is set to file, otherwise
no
Name of log file.
LogFileSize no 0-1024 1 Maximum size of log file in MB.
0 - disable automatic log rotation.
Note: If the log file size limit is reached and file rotation fails, for whatever reason, the existing log file is truncated and started anew.
LogType no file Log output type:
file - write log to file specified by LogFile parameter,
system - write log to syslog,
console - write log to standard output.
This parameter is supported since Zabbix 3.0.0.
LogRemoteCommands no 0 Enable logging of executed shell commands as warnings.
0 - disabled
1 - enabled
Commands will be logged only if executed remotely. Log entries will not be created if system.run[] is launched locally by HostMetadataItem, HostInterfaceItem or HostnameItem parameters.
MaxLinesPerSecond no 1-1000 20 Maximum number of new lines the agent will send per second to Zabbix server or proxy when processing 'log' and 'eventlog' active checks.
The provided value will be overridden by the parameter 'maxlines',
provided in 'log' or 'eventlog' item key.
Note: Zabbix will process 10 times more new lines than set in MaxLinesPerSecond to seek the required string in log items.
PidFile no /tmp/zabbix_agentd.pid Name of PID file.
RefreshActiveChecks no 60-3600 120 How often list of active checks is refreshed, in seconds.
Note that after failing to refresh active checks the next refresh will be attempted after 60 seconds.
Server yes, if StartAgents is not explicitly set to 0 List of comma delimited IP addresses, optionally in CIDR notation, or DNS names of Zabbix servers and Zabbix proxies.
Incoming connections will be accepted only from the hosts listed here.
If IPv6 support is enabled then '127.0.0.1', '::127.0.0.1', '::ffff:127.0.0.1' are treated equally and '::/0' will allow any IPv4 or IPv6 address.
'0.0.0.0/0' can be used to allow any IPv4 address.
Note that "IPv4-compatible IPv6 addresses" (0000::/96 prefix) are supported but deprecated by RFC4291.
Example: Server=127.0.0.1,192.168.1.0/24,::1,2001:db8::/32,zabbix.example.com
Spaces are allowed.
ServerActive no Zabbix server/proxy address to get active checks from.
Server/proxy address is IP address or DNS name and optional port separated by colon.
Multiple Zabbix servers and Zabbix proxies can be specified, separated by comma.
More than one Zabbix proxy should not be specified from each Zabbix server.
If Zabbix proxy is specified then Zabbix server for that proxy should not be specified.
Multiple comma-delimited addresses can be provided to use several independent Zabbix servers in parallel. Spaces are allowed.
If port is not specified, default port is used.
IPv6 addresses must be enclosed in square brackets if port for that host is specified.
If port is not specified, square brackets for IPv6 addresses are optional.
If this parameter is not specified, active checks are disabled.
Example: ServerActive=127.0.0.1:20051,zabbix.example.com,[::1]:30051,::1,[12fc::1].
SourceIP no Source IP address for:
- outgoing connections to Zabbix server or Zabbix proxy;
- making connections while executing some items (web.page.get, net.tcp.port, etc.)
StartAgents no 0-100 3 Number of pre-forked instances of zabbix_agentd that process passive checks.
If set to 0, disables passive checks and the agent will not listen on any TCP port.
The upper limit used to be 16 before version 1.8.5.
Timeout no 1-30 3 Spend no more than Timeout seconds on processing.
TLSAccept yes, if TLS certificate or PSK parameters are defined (even for unencrypted connection), otherwise no What incoming connections to accept. Used for a passive checks. Multiple values can be specified, separated by comma:
unencrypted - accept connections without encryption (default)
psk - accept connections with TLS and a pre-shared key (PSK)
cert - accept connections with TLS and a certificate
This parameter is supported since Zabbix 3.0.0.
TLSCAFile no Full pathname of a file containing the top-level CA(s) certificates for peer certificate verification, used for encrypted communications between Zabbix components.
This parameter is supported since Zabbix 3.0.0.
TLSCertFile no Full pathname of a file containing the agent certificate or certificate chain, used for encrypted communications with Zabbix components.
This parameter is supported since Zabbix 3.0.0.
TLSCipherAll no GnuTLS priority string or OpenSSL (TLS 1.2) cipher string. Override the default ciphersuite selection criteria for certificate- and PSK-based encryption.
Example: TLS_AES_256_GCM_SHA384:TLS_CHACHA20_POLY1305_SHA256:TLS_AES_128_GCM_SHA256
This parameter is supported since Zabbix 4.4.7.
TLSCipherAll13 no Cipher string for OpenSSL 1.1.1 or newer in TLS 1.3. Override the default ciphersuite selection criteria for certificate- and PSK-based encryption.
Example for GnuTLS: NONE:+VERS-TLS1.2:+ECDHE-RSA:+RSA:+ECDHE-PSK:+PSK:+AES-128-GCM:+AES-128-CBC:+AEAD:+SHA256:+SHA1:+CURVE-ALL:+COMP-NULL::+SIGN-ALL:+CTYPE-X.509
Example for OpenSSL: EECDH+aRSA+AES128:RSA+aRSA+AES128:kECDHEPSK+AES128:kPSK+AES128
This parameter is supported since Zabbix 4.4.7.
TLSCipherCert no GnuTLS priority string or OpenSSL (TLS 1.2) cipher string. Override the default ciphersuite selection criteria for certificate-based encryption.
Example for GnuTLS: NONE:+VERS-TLS1.2:+ECDHE-RSA:+RSA:+AES-128-GCM:+AES-128-CBC:+AEAD:+SHA256:+SHA1:+CURVE-ALL:+COMP-NULL:+SIGN-ALL:+CTYPE-X.509
Example for OpenSSL: EECDH+aRSA+AES128:RSA+aRSA+AES128
This parameter is supported since Zabbix 4.4.7.
TLSCipherCert13 no Cipher string for OpenSSL 1.1.1 or newer in TLS 1.3. Override the default ciphersuite selection criteria for certificate-based encryption.
This parameter is supported since Zabbix 4.4.7.
TLSCipherPSK no GnuTLS priority string or OpenSSL (TLS 1.2) cipher string. Override the default ciphersuite selection criteria for PSK-based encryption.
Example for GnuTLS: NONE:+VERS-TLS1.2:+ECDHE-PSK:+PSK:+AES-128-GCM:+AES-128-CBC:+AEAD:+SHA256:+SHA1:+CURVE-ALL:+COMP-NULL:+SIGN-ALL
Example for OpenSSL: kECDHEPSK+AES128:kPSK+AES128
This parameter is supported since Zabbix 4.4.7.
TLSCipherPSK13 no Cipher string for OpenSSL 1.1.1 or newer in TLS 1.3. Override the default ciphersuite selection criteria for PSK-based encryption.
Example: TLS_CHACHA20_POLY1305_SHA256:TLS_AES_128_GCM_SHA256
This parameter is supported since Zabbix 4.4.7.
TLSConnect yes, if TLS certificate or PSK parameters are defined (even for unencrypted connection), otherwise no How the agent should connect to Zabbix server or proxy. Used for active checks. Only one value can be specified:
unencrypted - connect without encryption (default)
psk - connect using TLS and a pre-shared key (PSK)
cert - connect using TLS and a certificate
This parameter is supported since Zabbix 3.0.0.
TLSCRLFile no Full pathname of a file containing revoked certificates. This parameter is used for encrypted communications with Zabbix components.
This parameter is supported since Zabbix 3.0.0.
TLSKeyFile no Full pathname of a file containing the agent private key used for encrypted communications with Zabbix components.
This parameter is supported since Zabbix 3.0.0.
TLSPSKFile no Full pathname of a file containing the agent pre-shared key used for encrypted communications with Zabbix components.
This parameter is supported since Zabbix 3.0.0.
TLSPSKIdentity no Pre-shared key identity string, used for encrypted communications with Zabbix server.
This parameter is supported since Zabbix 3.0.0.
TLSServerCertIssuer no Allowed server (proxy) certificate issuer.
This parameter is supported since Zabbix 3.0.0.
TLSServerCertSubject no Allowed server (proxy) certificate subject.
This parameter is supported since Zabbix 3.0.0.
UnsafeUserParameters no 0,1 0 Allow all characters to be passed in arguments to user-defined parameters.
0 - do not allow
1 - allow
The following characters are not allowed:
\ ' " ` * ? [ ] { } ~ $ ! & ; ( ) < > | # @
Additionally, newline characters are not allowed.
Supported since Zabbix 1.8.2.
User no zabbix Drop privileges to a specific, existing user on the system.
Only has effect if run as 'root' and AllowRoot is disabled.
This parameter is supported since Zabbix 2.4.0.
UserParameter no User-defined parameter to monitor. There can be several user-defined parameters.
Format: UserParameter=<key>,<shell command>
Note that shell command must not return empty string or EOL only.
Example: UserParameter=system.test,who|wc -l

See also

  1. Differences in the Zabbix agent configuration for active and passive checks starting from version 2.0.0