Welcome to the intro guide to dkron! This will explain how to setup dkron, how easy is to use it, what problems could it help you to solve, etc.
Dkron nodes can work in two modes, agents or servers.
A Dkron agent is a cluster member that can handle job executions, run your scripts and return the resulting output to the server.
A Dkron server is also a cluster member that send job execution queries to agents or other servers, so servers can execute jobs too.
The main distinction is that servers order job executions, can be used to schedule jobs, handles data storage and participate on leader election.
Dkron clusters have a leader, the leader is responsible of starting job execution queries in the cluster.
Any Dkron agent or server acts as a cluster member and it’s available to run scheduled jobs.
You can choose whether a job is run on a node or nodes by specifying tags and a count of target nodes having this tag do you want a job to run. This gives an unprecedented level of flexibility in runnig jobs across a cluster of any size and with any combination of machines you need.
All the execution responses will be gathered by the scheduler and stored in the database.
Dkron relies on the key-value store for data storage, you can run an instance of the distributed store in the same machines as Dkron or connect it to your existing cluster.
It can use etcd, Consul, or Zookeeper as data stores. To install any one of these systems, go to their web site:
deb [trusted=yes] https://apt.fury.io/victorcoder/ /
sudo apt-get install dkron-unstable
sudo apt-get install dkron
Simply download the packaged archive for your platform from the downloads page, extract the package to a shared location in your drive, like
/opt/local and run it from there.
See the configuration section.
By default Dkron uses the following ports:
8946for communicating between agents
8080for HTTP for the API and Dashboard
6868for RPC comunication between agents.
Be sure you have opened this ports (or the ones that you configured) in your firewall or AWS security groups.
By default dkron will try to use a local etcd server running in the same machine and in the default port. You can specify the store by setting the
backend-machines flag in the config file, env variables or as a command line flag.
To start a Dkron server instance just run:
dkron agent --server