In order to do so IPFS Cluster nodes use a libp2p-based consensus algorithm (currently Raft) to agree on a log of operations and build a consistent state across the cluster. The state represents which objects should be pinned by which nodes.
Additionally, cluster nodes act as a proxy/wrapper to the IPFS API, so they can be used as a regular node, with the difference that pin requests are handled by the Cluster.
Current functionality only allows pinning in all cluster members, but more strategies (like setting a replication factor for each pin) will be developed.
Since the start of IPFS it was clear that a tool to coordinate a number of different nodes (and the content they are supposed to store) would add a great value to the IPFS ecosystem. Naïve approaches are possible, but they present some weaknesses, specially at dealing with error handling, recovery and implementation of advanced pinning strategies.
`ipfs-cluster` aims to address this issues by providing a IPFS node wrapper which coordinates multiple cluster members via a consensus algorithm. This ensures that the desired state of the system is always agreed upon and can be easily maintained by the members of the cluster. Thus, every cluster member knows which content is tracked, can decide whether asking IPFS to pin it and can react to any contingencies like node reboots.
This project is captained by [@hsanjuan](https://github.com/hsanjuan). See the [captain's log](captain.log.md) for information about current status and upcoming features. You can also check out the project's [Roadmap](ROADMAP.md).
You can add the multiaddresses for the other members of the cluster in the `cluster_peers` variable. For example, here is a valid configuration for a cluster of 4 members:
The configuration file should probably be identical among all cluster members, except for the `id` and `private_key` fields. To facilitate configuration, `cluster_peers` includes its own address, but it does not have to.
`ipfs-cluster-ctl` is the client application to manage the cluster nodes and perform actions. `ipfs-cluster-ctl` uses the HTTP API provided by the nodes.
After installing, you can run `ipfs-cluster-ctl --help` to display general description and options, or alternatively `ipfs-cluster-ctl help [cmd]` to display
Documentation and examples on how to use IPFS Cluster from Go can be found in [godoc.org/github.com/ipfs/ipfs-cluster](https://godoc.org/github.com/ipfs/ipfs-cluster).
