You can use Cloud Eye to monitor cluster metrics of CSS in real time and quickly handle exceptions. For details about Cloud Eye, see the Cloud Eye User Guide.
Table 1 lists the metrics supported by CSS.
Table 1 Supported metrics
Calculates the disk usage of a CSS cluster.
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.