Linux Process Detector

The Linux process scanner could detect any process in Linux with finders. It has two modes:

REGEX: could define a regex to filter which processes declare to monitor.
AGENT_SENSOR: scan recent active agents which have process status hook.

After finding the process, it would collect the metadata of the process when the report to the backend.

Configuration

Name	Default	Environment Key	Description
process_discovery.scanner.period	3s	ROVER_PROCESS_DISCOVERY_SCAN_PERIOD	The period to detect the process.
process_discovery.scanner.mode	AGENT_SENSOR	ROVER_PROCESS_DISCOVERY_SCAN_MODE	The process detection modes of the scanner. Support “REGEX”, “AGENT_SENSOR”.
process_discovery.scanner.agent			Active when using the “AGENT_SENSOR” mode scanner.
process_discovery.scanner.agent.process_status_refresh_period	1m	ROVER_PROCESS_DISCOVERY_AGENT_PROCESS_STATUS_REFRESH_PERIOD	Set the agent refresh period.
process_discovery.scanner.regex			Active when using the “REGEX” mode scanner, it supports using multiple regex to matches difference processes.
process_discovery.scanner.regex.match_cmd		ROVER_PROCESS_DISCOVERY_REGEX_SCANNER_MATCH_CMD	Use regex string to locate the process from the command line of the process.
process_discovery.scanner.regex.layer	OS_LINUX	ROVER_PROCESS_DISCOVERY_REGEX_SCANNER_LAYER	The Layer of the process entity
process_discovery.scanner.regex.service_name		ROVER_PROCESS_DISCOVERY_REGEX_SCANNER_SERVICE_NAME	The Service Name of the process entity.
process_discovery.scanner.regex.instance_name	{{.Rover.HostIPV4 “en0”}}	ROVER_PROCESS_DISCOVERY_REGEX_SCANNER_INSTANCE_NAME	The Service Instance Name of the process entity, by default, the instance name is the host IP v4 address from “en0” net interface.
process_discovery.scanner.regex.process_name	{{.Process.ExeName}}	ROVER_PROCESS_DISCOVERY_REGEX_SCANNER_PROCESS_NAME	The Process Name of the process entity, by default, the process name is the executable name of the process.
process_discovery.scanner.regex.labels		ROVER_PROCESS_DISCOVERY_REGEX_SCANNER_LABELS	The Process Labels, used to aggregate similar process from service entity. Multiple labels split by “,”.

Agent Sensor Mode

Agent Sensor mode scanner could scan processes that have installed the skywalking agent and report them.

Process Status Hook File Protocol

The agent must be implemented the process status hook file protocol, then the rover could be collected the information on the process.

This protocol is mainly a metadata file, which contains the metadata of the process. It should be saved in: {TMPDIR}/apache_skywalking/process/{pid}/metadata.properties, and update modify time with the interval to keep alive, the content in the properties format as below:

Key	Type	Description
layer	string	this process layer.
service_name	string	this process service name.
instance_name	string	this process instance name.
process_name	string	this process process name, it’s same with the instance name.
properties	json	the properties in instance, the process labels also in the properties value.
labels	string	the process labels, multiple labels split by “,”.
language	string	current process language, which is `golang`.

Regex Mode

Regex mode scanner could define a regex to filter which process declare to monitor by command line. Multiple regexes can be defined to match different types of processes.

Note, that the duplicate processes entities cannot be reported. If multiple entities are generated, only one process will be reported. If the multiple finders could match the same process, only the first finder could be selected and reported.

Entity Builder

The metadata of the process could build by the Go Template to help dynamically build them, also, you could just configure it as the string value, and it still works.

These fields are supported using the template to build:

Service Name
Service Instance Name
Process NAme

Context

The context provides multiple functions for helping you build the process metadata.

Rover

Rover context provides the context of the rover process instance and VM data.

Name	Argument	Example	Description
InstanceID	None	`{{.Rover.InstanceID}}`	Get the Instance ID of the rover.
HostIPV4	The Interface name	`{{.Rover.HostIPV4 "en0"}}`	Get the ipv4 address from the appointed network interface name.
HostIPV6	The Interface name	`{{.Rover.HostIPV6 "en0"}}`	Get the ipv6 address from the appointed network interface name.
HostName	None	`{{.Rover.HostName}}`	Get the host name of current machine.

Finder

Finder context provides the context of the current process finder.

Name	Argument	Example	Description
Layer	None	`{{.Finder.Layer}}`	The layer of the current process which defines in the configuration
RegexMatchGroup	The index of the regex pattern	`{{.Finder.RegexMatchGroup 1}}`	When using the regex to match the process command line, it could use the group concept in the regex. This function could help you get the group value from it.

Process

Process context provides the context relate to which process is matched.

Name	Argument	Example	Description
ExeFilePath	None	`{{.Process.ExeFilePath}}`	The execute file path of process.
ExeName	None	`{{.Process.ExeName}}`	The execute file name.
CommandLine	None	`{{.Process.CommandLine}}`	The command line of process.
Pid	None	`{{.Process.Pid}}`	The id of the process.
WorkDir	None	`{{.Process.WorkDir}}`	The work directory path of the process.

skywalking-rover