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In OneFS 8.2 and later, the isi_array_d daemon replaces isi_boot_d from prior versions. Isi_array_d is based on the Paxos consensus protocol.
Paxos is used to manage the process of agreeing on a single, cluster-wide result among a group of potential transient nodes. Although no deterministic, fault-tolerant consensus protocol can guarantee progress in an asynchronous network, Paxos guarantees safety (consistency), and the conditions that could prevent it from making progress are difficult to trigger.