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:

• 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.

development working release

Download latest release from repo releases.

Example of installing into an existing COSI registered linux system.

cd /opt/circonus
mkdir -p agent/{sbin,etc}
cd agent
ln -s /opt/circonus/nad/etc/node-agent.d plugins
curl "https://github.com/circonus-labs/circonus-agent/releases/download/v0.1.2/circonus-agent_0.1.2_linux_64-bit.tar.gz" -o circonus-agent.tgz
tar zxf circonus-agent.tgz

To leverage the existing COSI/NAD installation, create a configuration file /opt/circonus/agent/etc/circonus-agent.toml (or use the corresponding command line options.)

[reverse]
enabled = true
cid = "cosi"

[api]
key = "cosi"

Ensure that NAD is not currently running (e.g. systemctl stop nad) and start circonus-agent sbin/circonus-agentd.

development testing notes

NOTE: See Vagrantfile for an example which bootstraps a centos7 vm.

1. Install go (on linux for example)
   1. curl "https://storage.googleapis.com/golang/go1.9.linux-amd64.tar.gz" -O
   2. sudo tar -C /usr/local -xzf go1.9.linux-amd64.tar.gz
   3. echo 'export PATH="$PATH:/usr/local/go/bin"' > /etc/profile.d/go.sh (root)
2. Setup go env & clone repo
   1. mkdir -p ~/godev/src/github.com/circonus-labs
   2. Set GOPATH="${HOME}/godev" in .bashrc
   3. Logout/login, verify go version && env | grep GOPATH
3. Install dep (go package dependency manager)
   1. go get -u github.com/golang/dep/cmd/dep
4. Clone repo and run dep
   1. cd $GOPATH/src/github.com/circonus-labs
   2. git clone https://github.com/circonus-labs/circonus-agent.git
   3. cd circonus-agent && dep ensure
5. Build
   1. go build
6. Install
   1. mkdir -p /opt/circonus/agent/sbin
   2. cp circonus-agent /opt/circonus/agent/sbin/circonus-agentd
7. Run
   1. /opt/circonus/agent/sbin/circonus-agentd -h for help
   2. example - on a system where cosi has already been run
      1. stop nad, if it is running
      2. run: /opt/circonus/agent/sbin/circonus-agentd -p /opt/circonus/nad/etc/node-agent.d -r -cid cosi -api-key cosi --log-pretty
      • -p use the existing nad plugins
      • --api-key cosi load api credentials from cosi installation
      • --reverse-cid cosi load check information from cosi installation
      • -r establish a reverse connection
      • --log-prety print formatted logging output to the terminal

Options

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

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.

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

Running

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.