Services#

Introduction#

Squirro consists of several services that are started and stopped individually. A detailed list of Squirro services is listed later on this page.

When a Squirro server is started, all the services are started automatically using the Linux init.d subsystem.

Interacting With Services#

Services are controlled with the service command on the Linux console. See Accessing Servers for more information.

The service command must be run as root. This can be done by either becoming root first (using sudo -i) or by prefixing every service command with the sudo command.

The first argument for the command is the service name to interact with, then the operation to execute.

Check Service Status#

The service status is returned with the status sub-command. For example:

[[email protected] ~]# service sqtopicd status
sqtopicd (pid  3164) is running...

Start Service#

If a service is not running, the start sub-command can be used to launch it.

[[email protected] ~]# service sqtopicd start
Starting sqtopicd:                                          [ OK ]

Stop Service#

[[email protected] ~]# service sqtopicd stop
Stopping sqtopicd:                                          [ OK ]

If you now execute the status sub-command, it will report the service as being stopped.

[[email protected] ~]# service sqtopicd status
sqtopicd is stopped

Restart Service#

The restart sub-command attempts to stop a service first and will then start it again.

[[email protected] ~]# service sqtopicd restart
Stopping sqtopicd:                                          [ OK ]
Starting sqtopicd:                                          [ OK ]

Services List#

The following services form part of Squirro or are built-in services that Squirro uses. They can all be controlled with the service command as shown in the previous section.

Name

Description

crond

Task runner that executed scheduled tasks regularly.

elasticsearch

Main data storage for indexed data.

mariadb

Relational database used for storage of metadata about Squirro projects.

nginx

Web server through which all the requests for the frontend and the Squirro services are served.

redis-server-cache

NoSQL database used for cache

redis-server

NoSQL database

sqclusterd

Controls multi-cluster setup of Squirro.

sqconfigurationd

Manages application configuration.

sqcontentd

Extracts relevant content from web pages. See Noise Removal in the Data Loading and Processing manual.

sqdatasourced

Manages data loading process. See Data Loading and Processing manual.

sqdigestmailerd

sqemailsenderd

Sends out emails on behalf of Squirro.

sqfilteringd

Handles search tagging rules. See Search Tagging and Alerting in the Data Loading and Processing manual.

sqfingerprintd

Manages the fingerprints (Smart Filters).

sqfrontendd

Frontend service, implementing the main web interface of Squirro.

sqingesterd

Refers to the Pipeline service. Manages the process of enriching and indexing data. See Pipeline Steps in the Data Loading and Processing manual.

sqmachinelearningd

sqplumberd

Executes pipelets as part of the pipeline. See Pipelets in the Data Loading and Processing manual.

sqproviderd

Endpoint for the providers to import data into the system. See Data Connectors in the Data Loading and Processing manual.

sqrelatedstoryd

Detects near-duplicates as part of the pipeline. See Near-Duplicate Detection in the Data Loading and Processing manual.

sqschedulerd

Executes scheduled jobs that the Squirro application needs to run.

sqthumblerd

Calculates thumbnails for item images that are displayed in Squirro.

sqtopicd

Endpoint for the Squirro API. See Working with Squirro APIs in the API Reference.

sqtopicproxyd

Internal web service access to some project metadata.

sqtrendsd

Endpoint for user management and authentication. See Authentication in the Reference manual.

squserd

squserproxyd

Internal web service access to some user data.

sqwebshotd

Analyzes web stories and identifies the most relevant image to use for visualization.