| A string of 32 or more characters used to encrypt sensitive properties on alerts and actions before they're stored in {es}. Third party credentials — such as the username and password used to connect to an SMTP service — are an example of encrypted properties. +
+
If not set, {kib} will generate a random key on startup, but all alert and action functions will be blocked. Generated keys are not allowed for alerts and actions because when a new key is generated on restart, existing encrypted data becomes inaccessible. For the same reason, alerts and actions in high-availability deployments of {kib} will behave unexpectedly if the key isn't the same on all instances of {kib}. +
+
Although the key can be specified in clear text in `kibana.yml`, it's recommended to store this key securely in the <<secure-settings,{kib} Keystore>>.
| A list of hostnames that {kib} is allowed to connect to when built-in actions are triggered. It defaults to `[*]`, allowing any host, but keep in mind the potential for SSRF attacks when hosts are not explicitly added to the allowed hosts. An empty list `[]` can be used to block built-in actions from making any external connections. +
Note that hosts associated with built-in actions, such as Slack and PagerDuty, are not automatically added to allowed hosts. If you are not using the default `[*]` setting, you must ensure that the corresponding endpoints are added to the allowed hosts as well.
| A list of action types that are enabled. It defaults to `[*]`, enabling all types. The names for built-in {kib} action types are prefixed with a `.` and include: `.server-log`, `.slack`, `.email`, `.index`, `.pagerduty`, and `.webhook`. An empty list `[]` will disable all action types. +
+
Disabled action types will not appear as an option when creating new connectors, but existing connectors and actions of that type will remain in {kib} and will not function.