3 Zabbix agent 2 protocol

Overview

This section provides information on:

Agent2 -> Server : active checks request
Server -> Agent2 : active checks response
Agent2 -> Server : agent data request
Server -> Agent2 : agent data response

Active checks request

The active checks request is used to obtain the active checks to be processed by agent. This request is sent by the agent upon start and then with RefreshActiveChecks inervals.

Field	Type	Value
request	string	`active checks`
host	string	Host name.
version	string	The agent version: <major>.<minor>.
host_metadata	string	The configuration parameter HostMetadata or HostMetadataItem metric value (optional).
interface	string	The configuration parameter HostInterface or HostInterfaceItem metric value (optional).
ip	string	The configuration parameter ListenIP first IP if set (optional).
port	number	The configuration parameter ListenPort value if set and not default agent listening port (optional).

Example:

{
         "request": "active checks",
         "host": "Zabbix server",
         "version": "6.0",
         "host_metadata": "mysql,nginx",
         "hostinterface": "zabbix.server.lan",
         "ip": "159.168.1.1",
         "port": 12050
       }

Active checks response

The active checks response is sent by the server back to agent after processing active checks request.

Field		Type	Value
response		string	`success` \| `failed`
info		string	Error information in the case of failure (optional).
data		array of objects	Active check items (optional).
	key	string	Item key with expanded macros.
	itemid	number	Item identifier.
	delay	string	Item update interval.
	lastlogsize	number	Item lastlogsize.
	mtime	number	Item mtime.
refresh_unsupported		number	Unsupported item refresh interval (agent version < 5.4).
regexp		array of objects	Global regular expressions (optional).
	name	string	Global regular expression name.
	expression	string	Global regular expression.
	expression_type	number	Global regular expression type.
	exp_delimiter	string	Global regular expression delimiter.
	case_sensitive	number	Global regular expression case sensitiviness setting.

Example:

{
         "response": "success",
         "data": [
           {
             "key": "log[/home/zabbix/logs/zabbix_agentd.log]",
             "itemid": 1234,
             "delay": "30s",
             "lastlogsize": 0,
             "mtime": 0
           },
           {
             "key": "agent.version",
             "itemid": 5678,
             "delay": "10m",
             "lastlogsize": 0,
             "mtime": 0
           }
         ]
       }

Agent data request

The agent data request contains the gathered item values.

Field		Type	Value
request		string	`agent data`
host		string	Host name.
version		string	The agent version: <major>.<minor>.
session		string	Unique session identifier generated each time when agent is started.
data		array of objects	Item values.
	id	number	The value identifier (incremental counter used for checking duplicated values in the case of network problems).
	itemid	number	Item identifier.
	value	string	The item value (optional).
	lastlogsize	number	The item lastlogsize (optional).
	mtime	number	The item mtime (optional).
	state	number	The item state (optional).
	source	string	The value event log source (optional).
	eventid	number	The value event log eventid (optional).
	severity	number	The value event log severity (optional).
	timestamp	number	The value event log timestamp (optional).
	clock	number	The value timestamp (seconds since Epoch).
	ns	number	The value timestamp nanoseconds.

Example:

{
         "request": "agent data",
         "data": [
           {
             "id": 1,
             "itemid": 5678,
             "value": "2.4.0",
             "clock": 1400675595,
             "ns": 76808644
           },
           {
             "id": 2,
             "itemid": 1234,
             "lastlogsize": 112,
             "value": " 19845:20140621:141708.521 Starting Zabbix Agent [<hostname>]. Zabbix 2.4.0 (revision 50000).",
             "clock": 1400675595,
             "ns": 77053975
           }
         ],
         "host": "Zabbix server",
         "version": "6.0",
         "sessionid": "1234456akdsjhfoui"
       }

Agent data response

The agent data response is sent by the server back to agent after processing the agent data request.

Field	Type	Value
response	string	`success` \| `failed`
info	string	Item processing results.

Example:

{
         "response": "success",
         "info": "processed: 2; failed: 0; total: 2; seconds spent: 0.003534"
       }

Heartbeat message

The heartbeat message is sent by an active agent to Zabbix server/proxy every HeartbeatFrequency seconds (configured in the Zabbix agent 2 configuration file).

It is used to monitor the availability of active checks.

{
         "request": "active check heartbeat",
         "host": "Zabbix server",
         "heartbeat_freq": 60
       }

Field	Type	Mandatory	Value
request	string	yes	`active check heartbeat`
host	string	yes	The host name.
heartbeat_freq	number	yes	The agent heartbeat frequency (HeartbeatFrequency configuration parameter).

Documentation

3 Zabbix agent 2 protocol

Overview

Active checks request

Active checks response

Agent data request

Agent data response

Heartbeat message