key

edit

This setting is required when using the allocation action.

action: allocation
description: "Apply shard allocation filtering rules to the specified indices"
options:
  key: ...
  value: ...
  allocation_type: ...
filters:
- filtertype: ...

The value of this setting should correspond to a node setting on one or more nodes in your cluster.

For example, you might have set

node.tag: myvalue

in your elasticsearch.yml file for one or more of your nodes. To match allocation in this case, set key to tag.

These special attributes are also supported:

attribute description

_name

Match nodes by node name

_host_ip

Match nodes by host IP address (IP associated with hostname)

_publish_ip

Match nodes by publish IP address

_ip

Match either _host_ip or _publish_ip

_host

Match nodes by hostname

There is no default value. This setting must be set by the user or an exception will be raised, and execution will halt.