Shards browser¶
The CrateDB Admin UI comes with a shards browser that provides you with a visual overview of all the shards in your cluster.
Table of contents
Screenshots¶
Here’s what a simple database might look like:
In this example, there is one primary column:
The blob column holds BLOB tables
The doc column holds regular document tables
The blob column lists a single table:
my_blobs
The doc column lists a single table:
tweets
Below this, the table has one row per node in the cluster. CrateDB automatically names unnamed nodes. In this instance, there is a single node named Monte Civetta.
In this example, the Monte Civetta node is holding the following shards:
Three shards for the table named
my_blobs
Four shards for the table named
tweets
Shards are colored to indicate their status and there is a color key at the top of the table.
The color of the shards in this example indicates that they are all primary shards and have been successfully started.
Features¶
- Shard ID display:
You can toggle the display of shard IDs by selecting or unselecting the Show Shard IDs checkbox.
- Shard status:
Each shard is colored according to its status:
- Started Primary (bright green):
This is a primary shard that has been successfully started, allocated to a node, and is available for querying.
- Started Replica (dark green):
This is a replica shard that has been successfully started, allocated to a node, and is available for querying.
- Initializing (dark yellow):
The shard is being initialized (i.e. being started).
- Relocating (dark red):
The shard is being relocated to another node.
CrateDB automatically rebalances your cluster for you. While a shard is being moved to another node, it is unavailable for use.
- Unassigned (gray):
The shard exists on disk, but has not yet been allocated to a node.