Maestro is a collection of tools that can be used for distributed performance testing. It is oriented towards testing of messaging oriented middleware (MOM), such as Apache ActiveMQ and its successor Apache Artemis , but can be extended to other performance test use cases.
Because Maestro forms a test cluster, it requires several components to run and deploying it can be tricky.
In order to simplify the development process as well as simplify it for users hoping to play with and run local tests, I created a set of containers (handled by Docker Compose) that can deploy a Maestro Test Cluster for local testing.
The process is extremely simple and you can go from 0 to the actual test execution in 3 commands (supposing docker-compose is already installed on your system):
There’s a lot of examples in the internet showing how you can obtain the IP address of a libvirt guest virtual machine. Most of the examples show how to do that when the network is using NAT forwarding (aka “Virtual Networks”).
However, how to do that if your setup is using Bridged Networking and your guests receive an IP address from an external DHCP server?
One idea is to install the read the DHCP leases file straight from the guest FS. You can do that by using the libguestfs-tools to cat the file within the image. For RHEL 6 (and CentOS 6 and similar distributions) the process is similar to this:
The MQTT (Message Queue Telemetry Transport) messaging protocol is a lightweight protocol well suited for the Internet of Things. It is a simple protocol and an ISO standard. It comes with an extensible reference documentation.
To help me learn about it and simplify my work flow, I created this cheat sheet (warning: PDF) which highlights the most relevant details about the protocol. You can also see it online here.
Fedora is a rock-solid stable, with a good selection of official and non-official packages. Just like many other distros, it still gives you the flexibility to adjust the system to your workflow. Here’s my basic steps to adjust it to my needs: