You can check elasticsearch cluster health by using (CURL) and Cluster API provieded by elasticsearch:
$ curl -XGET 'localhost:9200/_cluster/health?pretty'
This will give you the status and other related data you need.
{
"cluster_name" : "xxxxxxxx",
"status" : "green",
"timed_out" : false,
"number_of_nodes" : 2,
"number_of_data_nodes" : 2,
"active_primary_shards" : 15,
"active_shards" : 12,
"relocating_shards" : 0,
"initializing_shards" : 0,
"unassigned_shards" : 0,
"delayed_unassigned_shards" : 0,
"number_of_pending_tasks" : 0,
"number_of_in_flight_fetch" : 0
}