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allocation provides a snapshot of how shards have located around the
cluster and the state of disk usage.
% curl '192.168.56.10:9200/_cat/allocation?v' shards diskUsed diskAvail diskRatio ip node 1 5.6gb 72.2gb 7.8% 192.168.56.10 Jarella 1 5.6gb 72.2gb 7.8% 192.168.56.30 Solarr 1 5.5gb 72.3gb 7.6% 192.168.56.20 Adam II
Here we can see that each node has been allocated a single shard and that they’re all using about the same amount of space.