Pioreactors are able to be used as individual units, or in concert with other Pioreactors. In either case, a Pioreactor needs to be assigned as a leader. The leader unit controls other Pioreactors (and that may include itself), stores the database, hosts the web interface, and is the interface between users and the hardware.
A leader will communicate and control all the workers (non-leader Pioreactors) in the inventory. The inventory is a list of workers in your cluster, defined in the section
cluster.inventory in the
Workers can be active (available for running activities and housing cultures), or inactive. This is set with
0 respectively in the
When you want to remove a Pioreactor from your cluster, you can remove it from the list in available inventory in
cluster.inventory section in
Possible cluster topologies
A cluster can be made up of a single Pioreactor, or can be scaled to as many Pioreactors as you have. This gives us a few different possible topologies of what your cluster of Pioreactor(s) might look like.
- The simplest topology is when you have a single Pioreactor, and so the leader is the only worker.
2. When you have multiple Pioreactors, you can nominate one to be the leader node, and retain it as a worker, too:
3. You can also choose not to have the leader be a worker. This is useful if you have a spare Raspberry Pi without the Pioreactor hardware, or the number of Pioreactors grows large and you wish to keep one out of the inventory to focus on being a leader only.
How to edit roles
To tell the cluster which computer is the leader, you edit the
leader_hostname section (under
Inventory is assigned in
Adding new workers
See the instructions here to add new workers to your cluster.