Alation Actions¶

Customer Managed Applies to customer-managed instances of Alation

Server Admins and IT administrators can configure, operate, and diagnose an Alation instance using Alation actions. For example, you can use actions to deploy configurations, set up high availability (HA), and restart Alation components.

This page will introduce you to actions and explain how to use them.

Safe and Unsafe Actions¶

There are two categories of actions: safe and unsafe.

Safe actions won’t interrupt Alation services or cause downtime.
Unsafe actions require a restart of certain Alation components or Alation as a whole to take effect, which will cause downtime for users.

Important

Unsafe actions will cause a short service interruption for your users. Normally, Alation support or documentation will warn you when an action will cause downtime. Please follow your company’s change procedures when using unsafe actions.

Unsafe actions are often used during configuration, upgrades, enabling of new features, and debugging activities. Unsafe actions won’t harm your Alation instance, as long as you use them as directed. Be aware that Alation will be unusable until the unsafe action is complete. Sometimes you need to take additional steps to restore Alation to working order, such as restarting Alation components.

Using Actions¶

First you’ll use SSH to connect to the Alation host server and enter the shell. Then you can use the alation_action utility to run actions.

Accessing the Alation Shell¶

Use SSH to connect to the Alation server.
Enter the Alation shell using the following command:
```
sudo /etc/init.d/alation shell
```

Running Actions in the Alation Shell¶

You can run Alation actions from any location in the Alation shell using the alation_action utility. The general form is:

alation_action <action_name>

For example, to use the backup_all action, enter the following in the Alation shell:

alation_action backup_all

Note

Some actions require you to be acting as the alation user on the server. You can switch to the alation user by entering sudo su alation on the command line.

List of Common Actions¶

The following table shows the most common and most useful actions you may need to run. It doesn’t include every action.

Important

“Unsafe” actions will cause a short service interruption for your users. Normally, Alation support or documentation will warn you when an action will cause downtime. Please follow your company’s change procedures when using unsafe actions.

Action Name	Description	Safe?
apply_license	Looks for a license file in the location specified by the `alation.install.license.path` parameter in alation_conf and updates your Alation instance with your license’s expiration date and number of user seats. You can also update your license using the Upload License File button on the License page in Alation’s Admin Settings. You might use this action when installing Alation or when renewing your Alation license. You must restart Alation after running this action.	Unsafe
backup_all	Performs a backup of Alation. You must be acting as the alation user to perform this action. See Backup and Restore How-tos for more information.	Safe
cluster_add_slaves	Connects the Secondary as a slave to the Primary. Used when setting up HA and rejoining the cluster after updating Alation.	Unsafe
cluster_enter_master_mode	Puts the server in the master mode. The master server will be the Primary instance in the cluster. Used when setting up HA and rejoining the cluster after updating Alation.	Unsafe
cluster_enter_standalone_mode	Puts the server in standalone mode and separates it from the cluster. This will disable replication. Used with an existing HA cluster to reinitialize or update Alation or to disable HA. To update Alation without splitting the cluster, see Update HA Pair Configuration.	Unsafe
cluster_failover	When run on Secondary, puts the server in standalone mode and separates it from the cluster. Restarts all Alation services and rebuilds the Elasticsearch index. See Failover to Secondary for more information.	Unsafe
cluster_generate_keys	Generates keys that will enable replication between two Alation servers. Used when setting up HA or updating a legacy HA setup.	Unsafe
cluster_kvstore_copy	Copies the Primary server’s KVStore to the Secondary server. Used when setting up HA and updating <../../installconfig/Update/UpdateHAPairwithClusterSplitting> Alation.	Unsafe
cluster_replicate_files	Syncs files and configurations between Primary and Secondary one time. Used to verify replication after setting up HA, updating a legacy HA setup, or updating Alation.	Safe
cluster_replicate_postgres	This will shut down Postgres on Secondary, delete it, and create a replica of the Primary’s database. Used when setting up HA, updating Alation without splitting the cluster, and rejoining the cluster after updating Alation.	Unsafe
get_cluster_public_key	Prints the public ssh key which all computers in the cluster should use.	Safe
create_dump	Creates a snapshot of the system and gathers all logs together. Helpful when working with support to troubleshoot an issue.	Safe
create_saml_keys	Generates public and private certificates for setting up Alation to use SAML for authentication. See Configure Authentication with SAML from Alation Shell for more information.	Safe
deploy_conf_all	Writes settings from alation_conf to all other configuration files in the Alation chroot. There are other Alation actions that deploy specific settings to configuration files. See Using alation_conf for more information.	Safe
destructive_restore_all	Restores Alation from a backup. This action only works on a newly installed instance. This process can’t be undone. See Backup and Restore How-tos for more information.	Unsafe
disable_datadog	Disables the system health monitoring service (Datadog) and removes the Health Checks tab on the Alation Admin Settings page.	Safe
enable_datadog	Enables system health monitoring via Datadog at https://datadoghq.com and makes the Health Checks tab available on the Alation Admin Settings page.	Safe
rebuild_es_index	This will rebuild the Elasticsearch index immediately. Useful when Alation’s search capability isn’t functioning correctly. Use only when directed. The completion time depends on the Rosemeta size and may take hours or even days on large instances. You can check the rebuild_index task status in Admin Settings > Monitor > Active Tasks.	Safe
repair	Repairs some common Alation issues, which includes fixing some file permissions and forcing the Alation server’s time to sync with the Network Time Protocol server. See Alation Repair Tool.	Safe
restart_alation	Stops all Alation components needed to serve users, then starts them again.	Unsafe
scan_postgres	Scans the internal Alation database (Postgres) to identify corrupted indexes. Alation recommends running this scan once a week and reviewing the results. See How to Scan Postgres For Corrupted Indexes for more information.	Safe
start_alation	Starts all Alation components needed to serve users.	Unsafe
start_alation_analytics_postgres	Starts the Alation Analytics Postgres service (if Alation Analytics is enabled).	Unsafe
start_datadog_agent	Starts the Datadog service (if Datadog is enabled).	Unsafe
start_kvstore	Starts the KVStore service.	Unsafe
start_lineage	Starts the Lineage V3 service.	Unsafe
start_nginx	Starts the Nginx web server.	Unsafe
start_postgres	Starts the Alation Postgres service.	Unsafe
start_taskserver	Starts the Taskserver service.	Unsafe
start_uwsgi	Starts the uWSGI service.	Unsafe
status_alation	Shows the current status of all Alation components.	Safe
stop_alation	Stops all Alation components needed to serve users.	Unsafe
stop_alation_analytics_postgres	Stops the Alation Analytics Postgres service (if Alation Analytics is enabled).	Unsafe
stop_datadog_agent	Stops the Datadog service (if Datadog is enabled).	Unsafe
stop_kvstore	Stops the KVStore service.	Unsafe
stop_lineage	Stops the Lineage V3 service.	Unsafe
stop_nginx	Stops the Nginx web server.	Unsafe
stop_postgres	Stops the Alation Postgres service.	Unsafe
stop_taskserver	Stops the Taskserver service.	Unsafe
stop_uwsgi	Stops the uWSGI service.	Unsafe

Actions with Supervisor¶

Supervisor is a component of Alation that can run actions to start, stop, and check the status of specific components in the Alation application stack. Supervisor controls the following components:

Running Actions with Supervisor¶

Reuse component for accessing the Alation shell. Once in the Alation shell, use the alation_supervisor utility to run Supervisor actions. The general form is:

alation_supervisor <action_name> <component_name>

For example, to stop uWSGI, enter the following in the Alation shell:

alation_supervisor stop web:uwsgi

List of Supervisor Actions¶

The following table shows the four actions you can run with Supervisor.

Action Name	Description	Safe?
restart	Stops then starts the specified component(s).	Unsafe
start	Starts the specified component(s).	Unsafe
status	Gives the status of the specified component(s).	Safe
stop	Stops the specified component(s).	Unsafe

Component Names¶

The following table shows the component names that Supervisor recognizes. Some components are made up of several processes or sub-components. See below for information on controlling all sub-components at once.

Component	Component Names for Supervisor
Celery	celery:celery-alationanalytics_0 celery:celery-beat celery:celery-cognates_0 celery:celery-cognates_1 celery:celery-cognates_2 celery:celery-curation_0 celery:celery-default_0 celery:celery-default_1 celery:celery-default_2 celery:celery-domains_0 celery:celery-domains_small_0 celery:celery-downloads_0 celery:celery-downloads_1 celery:celery-fastqueue_0 celery:celery-fastqueue_1 celery:celery-fastqueue_2 celery:celery-flag-propagation_0 celery:celery-ingestion_0 celery:celery-lexicon_0 celery:celery-metrics_0 celery:celery-parsing_0 celery:celery-parsing_1 celery:celery-parsing_2 celery:celery-scheduling_0 celery:celery-search_0 celery:celery-search_bulk_0 celery:celery-stewardship_0 celery:celery-stewardship_1 celery:celery-thinqueue_0
Connector	java:connector
Elasticsearch	java:elasticsearch-<version> When using this command, substitute `<version>` with the specific Elasticsearch version of your Alation release. To find out the Elasticsearch version, check the value of the alation_conf parameter `elasticsearch.version`.
Event Bus	event-bus:kafka-server event-bus:zookeeper-server event-bus-backup:kafka-mm2 event-bus-backup:kafka-secondary-server event-bus-backup:zookeeper-secondary-server
KVStore	kvstore
Lineage	lineage
Taskserver	java:taskserver
uWSGI	web:uwsgi

Referring to More Than One Component¶

Supervisor can control several components at once. You can list more than one component separated by a space. For example, to restart uWSGI and Elasticsearch, enter:

alation_supervisor restart web:uwsgi java:elasticsearch

For components that have sub-components, such as Celery, you can refer to all sub-components by putting an asterisk after the colon. For example:

alation_supervisor restart celery:*

To run the action on all components controlled by Supervisor, you can use the keyword “all” as the component name. For example:

alation_supervisor status all

Controlling Components without Actions¶

Redis is a component of Alation that can’t be controlled using Supervisor or the alation_action utility. To start or stop Redis individually, use the following commands.

sudo /etc/init.d/redis-server start
sudo /etc/init.d/redis-server stop

Redis can also be restarted along with all other components using the restart_alation action.