circonus-agent

README

Circonus Agent

NOTE: This is an "in development" project. As such, there are a few things to be aware of at this time...

Caveats:

• The code is changing frequently - please ensure the latest release is being used
• No target specific packages. (e.g. rpm|deb|pkg)
• No service configurations provided. (e.g. systemd, upstart, init, svc)
• Native plugins (.js) do not work. Unless modified to run node independently and follow plugin output guidelines

Features

1. Plugin architecture for local metric collection
2. Local HTTP Receiver for POST/PUT metric collection
3. Local StatsD listener for application metrics

Quick Start

Installing on a system which has already had cosi install and configure NAD.

1. mkdir -p /opt/circonus/agent/{sbin,etc}
2. Download latest release from repository (or build manually)
3. If downloaded, extract archive into /opt/circonus/agent
4. Stop NAD (e.g. systemctl stop nad)
5. Create a config or use command line parameters
6. Run sbin/circonus-agentd

Example, minimal, configuration using existing cosi install /opt/circonus/agent/etc/circonus-agent.toml:

# set the plugin directory to NAD's
plugin-dir = "/opt/circonus/nad/etc/node-agent.d"

[reverse]
enabled = true
cid = "cosi" # use cosi system check bundle

[api]
key = "cosi" # use cosi api configuration

#debug = true

Options

$ /opt/circonus/agent/sbin/circonus-agentd -h

Flags:
      --api-app string                       [ENV: CA_API_APP] Circonus API Token app (default "circonus-agent")
      --api-ca-file string                   [ENV: CA_API_CA_FILE] Circonus API CA certificate file
      --api-key string                       [ENV: CA_API_KEY] Circonus API Token key
      --api-url string                       [ENV: CA_API_URL] Circonus API URL (default "https://api.circonus.com/v2/")
  -c, --config string                        config file (default is /opt/circonus/agent/etc/circonus-agent.(json|toml|yaml)
  -d, --debug                                [ENV: CA_DEBUG] Enable debug messages
      --debug-cgm                            [ENV: CA_DEBUG_CGM] Enable CGM & API debug messages
  -h, --help                                 help for circonus-agent
  -l, --listen string                        [ENV: CA_LISTEN] Listen address and port [[IP]:[PORT]] (default ":2609")
      --log-level string                     [ENV: CA_LOG_LEVEL] Log level [(panic|fatal|error|warn|info|debug|disabled)] (default "info")
      --log-pretty                           [ENV: CA_LOG_PRETTY] Output formatted/colored log lines
      --no-statsd                            [ENV: CA_NO_STATSD] Disable StatsD listener
  -p, --plugin-dir string                    [ENV: CA_PLUGIN_DIR] Plugin directory (default "/opt/circonus/agent/plugins")
  -r, --reverse                              [ENV: CA_REVERSE] Enable reverse connection
      --reverse-broker-ca-file string        [ENV: CA_REVERSE_BROKER_CA_FILE] Broker CA certificate file
      --reverse-cid string                   [ENV: CA_REVERSE_CID] Check Bundle ID for reverse connection
      --reverse-create-check                 [ENV: CA_REVERSE_CREATE_CHECK] Create check bundle for reverse if one cannot be found
      --reverse-create-check-broker string   [ENV: CA_REVERSE_CREATE_CHECK_BROKER] ID of Broker to use or 'select' for random selection of valid broker, if creating a check bundle (default "select")
      --reverse-create-check-tags string     [ENV: CA_REVERSE_CREATE_CHECK_TAGS] Tags [comma separated list] to use, if creating a check bundle
      --reverse-create-check-title string    [ENV: CA_REVERSE_CREATE_CHECK_TITLE] Title [display name] to use, if creating a check bundle (default "<reverse-target> /agent")
      --reverse-target string                [ENV: CA_REVERSE_TARGET] Target host (default hostname)
      --show-config                          Show config and exit
      --ssl-cert-file string                 [ENV: CA_SSL_CERT_FILE] SSL Certificate file (PEM cert and CAs concatenated together) (default "/opt/circonus/agent/etc/circonus-agent.pem")
      --ssl-key-file string                  [ENV: CA_SSL_KEY_FILE] SSL Key file (default "/opt/circonus/agent/etc/circonus-agent.key")
      --ssl-listen string                    [ENV: CA_SSL_LISTEN] SSL listen address and port [IP]:[PORT] - setting enables SSL
      --ssl-verify                           [ENV: CA_SSL_VERIFY] Enable SSL verification (default true)
      --statsd-group-cid string              [ENV: CA_STATSD_GROUP_CID] StatsD group check bundle ID
      --statsd-group-counters string         [ENV: CA_STATSD_GROUP_COUNTERS] StatsD group metric counter handling (average|sum) (default "sum")
      --statsd-group-gauges string           [ENV: CA_STATSD_GROUP_GAUGES] StatsD group gauge operator (default "average")
      --statsd-group-prefix string           [ENV: CA_STATSD_GROUP_PREFIX] StatsD group metric prefix (default "group.")
      --statsd-group-sets string             [ENV: CA_STATSD_GROPUP_SETS] StatsD group set operator (default "sum")
      --statsd-host-cateogry string          [ENV: CA_STATSD_HOST_CATEGORY] StatsD host metric category (default "statsd")
      --statsd-host-prefix string            [ENV: CA_STATSD_HOST_PREFIX] StatsD host metric prefix (default "host.")
      --statsd-port string                   [ENV: CA_STATSD_PORT] StatsD port (default "8125")
  -V, --version                              Show version and exit

Config

YAML

---
debug: false
debug_cgm: false
listen: ":2609"
plugin-dir: "/opt/circonus/agent/plugins"

api:
  app: circonus-agent
  ca_file: ''
  key: ''
  url: https://api.circonus.com/v2/

log:
  level: info
  pretty: false

reverse:
  enabled: false
  broker_ca_file: ''
  check_bundle_id: ''
  check_target: localhost
  create_check: false
  check:
    broker: select
    tags: ''
    title: localhost /agent

ssl:
  cert_file: "/opt/circonus/agent/etc/circonus-agent.pem"
  key_file: "/opt/circonus/agent/etc/circonus-agent.key"
  listen: ''
  verify: true

statsd:
  disabled: false
  port: '8125'
  group:
    check_bundle_id: ''
    counters: sum
    gauges: average
    metric_prefix: group.
    sets: sum
  host:
    category: statsd
    metric_prefix: host.

TOML

debug = false
debug_cgm = false
listen = ":2609"
plugin-dir = "/opt/circonus/agent/plugins"

[api]
app = "circonus-agent"
ca_file = ""
key = ""
url = "https://api.circonus.com/v2/"

[log]
level = "info"
pretty = false

[reverse]
enabled = false
broker_ca_file = ""
check_bundle_id = ""
check_target = "localhost"
create_check = false
[reverse.check]
broker = "select"
tags = ""
title = "localhost /agent"

[ssl]
cert_file = "/opt/circonus/agent/etc/circonus-agent.pem"
key_file = "/opt/circonus/agent/etc/circonus-agent.key"
listen = ""
verify = true

[statsd]
disabled = false
port = '8125'

[statsd.group]
check_bundle_id = ""
counters = "sum"
gauges = "average"
metric_prefix = "group."
sets = "sum"

[statsd.host]
category = "statsd"
metric_prefix = "host."

JSON

{
   "api": {
     "app": "circonus-agent",
     "ca_file": "",
     "key": "",
     "url": "https://api.circonus.com/v2/"
   },
   "debug": false,
   "debug_cgm": false,
   "listen": ":2609",
   "log": {
     "level": "info",
     "pretty": false
   },
   "plugin-dir": "/opt/circonus/agent/plugins",
   "reverse": {
     "broker_ca_file": "",
     "check": {
       "broker": "select",
       "tags": "",
       "title": "localhost /agent"
     },
     "check_bundle_id": "",
     "check_target": "localhost",
     "create_check": false,
     "enabled": false
   },
   "ssl": {
     "cert_file": "/opt/circonus/agent/etc/circonus-agent.pem",
     "key_file": "/opt/circonus/agent/etc/circonus-agent.key",
     "listen": "",
     "verify": true
   },
   "statsd": {
     "disabled": false,
     "group": {
       "check_bundle_id": "",
       "counters": "sum",
       "gauges": "average",
       "metric_prefix": "group.",
       "sets": "sum"
     },
     "host": {
       "category": "statsd",
       "metric_prefix": "host."
     },
     "port": "8125"
   }
 }

Plugins

• Go in the --plugin-dir.
• Must be regular files or symlinks.
• Must be executable (e.g. 0755)
• Files are expected to be named matching a pattern of: <base_name>.<ext> (e.g. foo.sh)
• Directories are ignored.
• Configuration files are ignored.
  • Configuration files are defined as files with extensions of .json or .conf
  • A .json file is assumed to be a configuration for a plugin with the same base_name (e.g. foo.json is a configuration for foo.sh, foo.elf, etc.)
    • JSON config files are loaded and arguments defined are passed to the plugin instance(s).
    • The format for JSON config files is: {"instance_id": ["arg1", "arg2", ...], ...}.
    • One instance of the plugin will be run for each distinct instance_id found in the JSON.
    • The format of the resulting metric names would be: plugin`instance_id`metric_name
  • A .conf file is assumed to be a shell configuration file which is loaded by the plugin itself.
• All other directory entries are ignored.

Running plugin environment

When plugins are executed, the current working directory will be set to the --plugin-dir, for relative path references to find configs or data files. Scripts may safely reference $PWD. See plugin_test/write_test/wtest1.sh for example. In plugin_test, run ln -s write_test/wtest1.sh, start the agent (e.g. go run main.go -p plugin_test), then curl localhost:2609/ to see it in action.

Plugin Output

Output from plugins is expected on stdout either tab-delimited or json.

Tab delimited

metric_name<TAB>metric_type<TAB>metric_value

JSON

{
    "metric_name": {
        "_type": "metric_type",
        "_value": "metric_value"
    },
    ...
}

Metric types

Type	Description
i	signed 32-bit integer
I	unsigned 32-bit integer
l	signed 64-bit integer
L	unsigned 64-bit integer
n	double/float
s	string/text

Receiver

The circonus-agent listens at a special endpoint /write for HTTP POST and HTTP PUT requests containing structured JSON. The structure of the JSON expected follows the plugin JSON format.

The URL syntax for sending metrics is /write/ID where ID is a prefix for all of the metrics being sent in the request.

For example:

HTTP POST http://127.0.0.1:2609/write/test with a payload of:

{
    "t1": {
        "_type": "i",
        "_value": 32
    },
    "t2": {
        "_type": "s",
        "_value": "foo"
    }
}

Would result in metrics in the Circonus UI of:

test`t1 numeric 32
test`t2 text "foo"

StatsD

The circonus-agent provides a StatsD listener by default (disable: --no-statsd, configure port: --statsd-port). It accepts the basic StatsD metric types as well as, Circonus specific metric types h and t.

Type	Note
c	Counter
g	Gauge
h	Histogram - Circonus specific
ms	Timing - treated as a Histogram
s	Sets - treated as a Counter
t	Text - Circonus specific

NOTE: the derivative metrics automatically generated with some StatsD types are not created by Circonus, as the data is already available.

Manual build

1. Clone repo git clone https://github.com/circonus-labs/circonus-agent.git
2. Dependencies, run dep ensure (requires dep utility)
3. Build go build -o circonus-agentd
4. Install cp circonus-agentd /opt/circonus/agent/sbin