lucene/solr/solr-ref-guide/src/cloud-screens.adoc

= Cloud Screens
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When running in <<solrcloud.adoc#solrcloud,SolrCloud>> mode, a "Cloud" option will appear in the Admin UI between <<logging.adoc#logging,Logging>> and <<collections-core-admin.adoc#collections-core-admin,Collections>>.

This screen provides status information about each collection & node in your cluster, as well as access to the low level data being stored in <<using-zookeeper-to-manage-configuration-files.adoc#using-zookeeper-to-manage-configuration-files,ZooKeeper>>.

.Only Visible When using SolrCloud
[NOTE]
====
The "Cloud" menu option is only available on Solr instances running in <<getting-started-with-solrcloud.adoc#getting-started-with-solrcloud,SolrCloud mode>>. Single node or master/slave replication instances of Solr will not display this option.
====

Click on the Cloud option in the left-hand navigation, and a small sub-menu appears with options called "Tree", "Graph", and "Graph (Radial)". The default view ("Graph") shows a graph of each collection, the shards that make up those collections, and the addresses and type ("NRT", "TLOG" or "PULL") of each replica for each shard.

This example shows a simple cluster. In addition to the 2 shard, 2 replica "gettingstarted" collection, there is an additional "tlog" collection consisting of mixed TLOG and PULL replica types.

image::images/cloud-screens/cloud-graph.png[image,width=512,height=250]

Tooltips appear when hovering over each replica giving additional information.

image::images/cloud-screens/cloud-hover.png[image,width=512,height=250]

The "Graph (Radial)" option provides a different visual view of each node. Using the same example cluster, the radial graph view looks like:

image::images/cloud-screens/cloud-radial.png[image,width=478,height=250]

The "Tree" option shows a directory structure of the data in ZooKeeper, including cluster wide information regarding the `live_nodes` and `overseer` status, as well as collection specific information such as the `state.json`, current shard leaders, and configuration files in use. In this example, we see part of the `state.json`  definition for the "tlog" collection:

image::images/cloud-screens/cloud-tree.png[image,width=487,height=250]

As an aid to debugging, the data shown in the "Tree" view can be exported locally using the following command `bin/solr zk ls -r /`