Upgrading IPFS Cluster

The IPFS Cluster project releases new versions regularly. This  section describes the procedure to upgrade Clusters with minimal or no  downtime.

The main consideration is that:

All the cluster peers need to run the same cluster `major.minor` (but they can have different patch numbers). i.e.: 0.10.x or 0.11.x.

Otherwise, peers will not be able to communicate. We plan to move to a more flexible scheme soon, as the feature set stabilizes.

The general approach to is to:

1. Replace ipfs-cluster-ctl and ipfs-cluster-service with their new versions.
2. Restart all the peers.

For compatible versions (patch bumps), this can be done gradually without general downtime.

In the case of raft, this only works if:

• leave_on_shutdown is set to false. Otherwise, those peer will need to be bootstrapped on the next start.
• wait_for_leader_timeout is sufficiently high to account for the restart of all peers (default should be ok in most cases)