Describe the feature: Improve the "Disk Available" value on the main "Monitoring" page, by only counting the free disk space on nodes that have node.data=true in their config.
Elasticsearch version: Version: 5.6.2, Build: 57e20f3/2017-09-23T13:16:45.703Z, JVM: 1.8.0_131
Plugins installed: [x-pack]
JVM version : 1.8.0_131
OS version : RHEL7
Description of the problem including expected versus actual behavior:
The "Disk Available" value on the main "Monitoring" page displays the sum of free disk space on all the nodes in the cluster, even if those nodes don't have the node.data setting to 'true'. The resulting value could be misleading.
Example: This morning, I had a red cluster state, caused by shards that couldn't be allocated because of no disk space left...and at this moment, the "Disk Available" value was 20% (because I have several non data nodes included in that value).
Thanks in advance!