Used disk space of a cluster/Total disk space of a cluster
0 to 100%
Cluster Health Status
Measures the health status of a CSS cluster.
Available values are 0, 1, and 2.
0: All primary and replica shards are allocated. Your cluster is 100% operational.
1: All primary shards are allocated, but at least one replica is missing. No data is missing, so search results will still be complete. However, high availability is compromised to some degree. If more shards disappear, you might lose data. Think of this status as a warning that should prompt investigation.
2: At least one primary shard (and all of its replicas) is missing. This means that you are missing data: searches will return partial results, and indexing into that shard will return an exception.