Virgo

Virgo is a project for building an on-host agents. The goal is to provide shared infrastructure for various types of agents.

The first agent to use this infrastructure is the Rackspace Cloud Monitoring agent.

Join in and build your agent with us.

License

virgo is distributed under the Apache License 2.0.

Bundles

Bundles take the form [name]-[version].zip, ie:

monitoring-0.0.1.zip

A command-line argument of '-b' will force a specific bundle directory.

Versioning

The agent is versioned with a three digit dot seperated "semantic version" with the template being x.y.z. An example being e.g. 1.4.2. The rough meaning of each of these parts are:

• major version numbers will change when we make a backwards incompatible change to the bundle format. Binaries can only run bundles with identical major version numbers. e.g. a binary of version 2.3.1 can only run bundles starting with 2.

• minor version numbers will change when we make backwards compatible changes to the bundle format. Binaries can only run bundles with minor versions that are greater than or equal to the bundle version. e.g. a binary of version 2.3.1 can run a 2.3.4 bundle but not a 2.2.1 bundle.

• patch version numbers will change everytime a new bundle is released. It has no semantic meaning to the versioning.

The zip file bundle and the binary shipped in an rpm/deb/msi will be identical. If the binary is 1.4.2 then the bundle will be 1.4.2.

Building on a Unix-like Operating System

./configure
make

Running tests

make test

Running monitoring agent fixtures server

The monitoring agent comes with an example fixture server. This will send the fixtures found in agents/monitoring/tests/fixtures/ back and forth between a running agent. You can run a server and agent like this:

 python agents/monitoring/runner.py server_fixture
 python agents/monitoring/runner.py agent_fixture

If you want to have the fixtures server listen on something other than 127.0.0.1 provide the environment variable LISTEN_IP="0.0.0.0".

Building for Rackspace Cloud Monitoring

Rackspace customers: Virgo is the open source project for the Rackspace Cloud Monitoring agent. Feel free to build your own copy from this source.

But! Please don't contact Rackspace Support about issues you encounter with your custom build. We can't support every change people may make and master might not be fully tested.

Building on RHEL 5.x

Add the EPEL repo and install dependencies

# rpm -ivh http://mirror.hiwaay.net/pub/epel/5/x86_64/epel-release-5-4.noarch.rpm
# yum update
# yum groupinstall 'Development Tools'
# yum install git python26 gcc44 gcc44-c++

Default to python2.6:

# ln -s /usr/bin/python2.6 /usr/local/bin/python
# export PATH=/usr/local/bin:$PATH

Clone the repository:

# git clone https://github.com/racker/virgo.git

Configure and Build:

# ./configure
# CC=gcc44 CXX=g++44 make
# CC=gcc44 CXX=g++44 make install

Building on Windows

Install the following:

• Windows .NET 4 Framework (Full Framework, not client): http://www.microsoft.com/download/en/details.aspx?displaylang=en&id=17851
• Python 2.7: http://www.python.org/download/releases/2.7.3/
• MSYS Git: http://code.google.com/p/msysgit/downloads/list?q=full+installer+official+git (does not work with cygwin git)
• Windows 7 SDK: https://www.microsoft.com/download/en/details.aspx?id=8279
• VS 2010 C++ Express: http://www.microsoft.com/visualstudio/en-us/products/2010-editions/visual-cpp-express
• VS 2010 SP1: https://www.microsoft.com/download/en/details.aspx?id=23691

Once the dependencies are installed:

python configure

Now you can open monitoring-agent.sln from Visual Studio.

If you wish to compile from the command line, run:

python tools/build.py build

See also: http://www.chromium.org/developers/how-tos/build-instructions-windows

Hacking

Change agent entry point

The entry point to the agent defaults to modules/monitoring/monitoring-agent.lua. To change this entry use the flag -e:

./monitoring-agent -z monitoring-test.zip -e tests

This example would run agents/monitoring/tests/init.lua.

Making a new release

Virgo version numbers are managed using git tagging. To make a new version create an annotated tag:

git tag -a 0.1.1 -m 'release v0.1.1'

Then push the tag to your git repository

git push --tags

State Machine Diagram

The textual representation of the dot file is generated with Graph-Easy.

https://github.com/ironcamel/Graph-Easy

Command:

graph-easy --input=contrib/fsm.gv --output=contrib/fsm.txt --as_ascii

Distro Packages

RPM

yum install rpm-build
make rpm

Find the rpms in out/rpmbuild/RPMS/

dpkg

apt-get install devscripts
make deb

Find the deb in out/debbuild/