Remote V2 Connectors - Lucidworks documentation

This article describes features or functionality that are only compatible with Fusion 5.6 and later.

Remote V2 connectors let you index data behind firewalls. Fusion uses gRPC over HTTP/2 communication to bridge between firewalled on-premises remote connectors and Fusion clusters. This page explains some of the concepts around remote connectors.

Configure Remote V2 Connectors

If you need to index data from behind a firewall, you can configure a V2 connector to run remotely on-premises using TLS-enabled gRPC.

Prerequisites

Before you can set up an on-prem V2 connector, you must configure the egress from your network to allow HTTP/2 communication into the Fusion cloud. You can use a forward proxy server to act as an intermediary between the connector and Fusion.The following is required to run V2 connectors remotely:

The plugin zip file and the connector-plugin-standalone JAR.
A configured connector backend gRPC endpoint.
Username and password of a user with a remote-connectors or admin role.
If the host where the remote connector is running is not configured to trust the server’s TLS certificate, you must configure the file path of the trust certificate collection.

If your version of Fusion doesn’t have the remote-connectors role by default, you can create one. No API or UI permissions are required for the role.

Connector compatibility

Only V2 connectors are able to run remotely on-premises. You also need the remote connector client JAR file that matches your Fusion version. You can download the latest files at V2 Connectors Downloads.

Whenever you upgrade Fusion, you must also update your remote connectors to match the new version of Fusion.

The gRPC connector backend is not supported in Fusion environments deployed on AWS.

System requirements

The following is required for the on-prem host of the remote connector:

(Fusion 5.9.0-5.9.10) JVM version 11
(Fusion 5.9.11 and later) JVM version 17
Minimum of 2 CPUs
4GB Memory

Note that memory requirements depend on the number and size of ingested documents.

Enable backend ingress

In your values.yaml file, configure this section as needed:

ingress:
  enabled: false
  pathtype: "Prefix"
  path: "/"
  #host: "ingress.example.com"
  ingressClassName: "nginx"   # Fusion 5.9.6 only
  tls:
    enabled: false
    certificateArn: ""
    # Enable the annotations field to override the default annotations
    #annotations: ""

Set enabled to true to enable the backend ingress.
Set pathtype to Prefix or Exact.
Set path to the path where the backend will be available.
Set host to the host where the backend will be available.
In Fusion 5.9.6 only, you can set ingressClassName to one of the following:
- nginx for Nginx Ingress Controller
- alb for AWS Application Load Balancer (ALB)
Configure TLS and certificates according to your CA’s procedures and policies.
TLS must be enabled in order to use AWS ALB for ingress.

Connector configuration example

kafka-bridge:
  target: mynamespace-connectors-backend.lucidworkstest.com:443 # mandatory
  plain-text: false # optional, false by default.  
    proxy-server: # optional - needed when a forward proxy server is used to provide outbound access to the standalone connector
    host: host
    port: some-port
    user: user # optional
    password: password # optional
  trust: # optional - needed when the client's system doesn't trust the server's certificate
    cert-collection-filepath: path1

proxy: # mandatory fusion-proxy
  user: admin
  password: password123
  url: https://fusiontest.com/ # needed only when the connector plugin requires blob store access

plugin: # mandatory
  path: ./fs.zip
  type: #optional - the suffix is added to the connector id
    suffix: remote

Minimal example

kafka-bridge:
  target: mynamespace-connectors-backend.lucidworkstest.com:443

proxy:
  user: admin
  password: "password123"

plugin:
  path: ./testplugin.zip

Logback XML configuration file example

<configuration>
    <appender name="CONSOLE" class="ch.qos.logback.core.ConsoleAppender">
        <encoder class="com.lucidworks.logging.logback.classic.LucidworksPatternLayoutEncoder">
            <pattern>%d - %-5p [%t:%C{3.}@%L] - %m{nolookups}%n</pattern>
            <charset>utf8</charset>
        </encoder>
    </appender>

    <appender name="FILE" class="ch.qos.logback.core.rolling.RollingFileAppender">
        <file>${LOGDIR:-.}/connector.log</file>
        <rollingPolicy class="ch.qos.logback.core.rolling.SizeAndTimeBasedRollingPolicy">
            <!-- rollover daily -->
            <fileNamePattern>${LOGDIR:-.}/connector-%d{yyyy-MM-dd}.%i.log.gz</fileNamePattern>
            <maxFileSize>50MB</maxFileSize>
            <totalSizeCap>10GB</totalSizeCap>
        </rollingPolicy>
        <encoder class="com.lucidworks.logging.logback.classic.LucidworksPatternLayoutEncoder">
            <pattern>%d - %-5p [%t:%C{3.}@%L] - %m{nolookups}%n</pattern>
            <charset>utf8</charset>
        </encoder>
    </appender>

    <root level="INFO">
        <appender-ref ref="CONSOLE"/>
        <appender-ref ref="FILE"/>
    </root>
</configuration>

Run the remote connector

java [-Dlogging.config=[LOGBACK_XML_FILE]] \
  -jar connector-plugin-client-standalone.jar [YAML_CONFIG_FILE]

The logging.config property is optional. If not set, logging messages are sent to the console.

Test communication

You can run the connector in communication testing mode. This mode tests the communication with the backend without running the plugin, reports the result, and exits.

java -Dstandalone.connector.connectivity.test=true -jar connector-plugin-client-standalone.jar [YAML_CONFIG_FILE]

Encryption

In a deployment, communication to the connector’s backend server is encrypted using TLS. You should only run this configuration without TLS in a testing scenario. To disable TLS, set plain-text to true.

Egress and proxy server configuration

One of the methods you can use to allow outbound communication from behind a firewall is a proxy server. You can configure a proxy server to allow certain communication traffic while blocking unauthorized communication. If you use a proxy server at the site where the connector is running, you must configure the following properties:

Host. The hosts where the proxy server is running.
Port. The port the proxy server is listening to for communication requests.
Credentials. Optional proxy server user and password.

When you configure egress, it is important to disable any connection or activity timeouts because the connector uses long running gRPC calls.

Password encryption

If you use a login name and password in your configuration, run the following utility to encrypt the password:

Enter a user name and password in the connector configuration YAML.

Run the standalone JAR with this property:

-Dstandalone.connector.encrypt.password=true

Retrieve the encrypted passwords from the log that is created.
Replace the clear password in the configuration YAML with the encrypted password.

Connector restart (5.7 and earlier)

The connector will shut down automatically whenever the connection to the server is disrupted, to prevent it from getting into a bad state. Communication disruption can happen, for example, when the server running in the connectors-backend pod shuts down and is replaced by a new pod. Once the connector shuts down, connector configuration and job execution are disabled. To prevent that from happening, you should restart the connector as soon as possible.You can use Linux scripts and utilities to restart the connector automatically, such as Monit.

Recoverable bridge (5.8 and later)

If communication to the remote connector is disrupted, the connector will try to recover communication and gRPC calls. By default, six attempts will be made to recover each gRPC call. The number of attempts can be configured with the max-grpc-retries bridge parameters.

Job expiration duration (5.9.5 only)

The timeout value for irresponsive backend jobs can be configured with the job-expiration-duration-seconds parameter. The default value is 120 seconds.

Use the remote connector

Once the connector is running, it is available in the Datasources dropdown. If the standalone connector terminates, it disappears from the list of available connectors. Once it is re-run, it is available again and configured connector instances will not get lost.

Enable asynchronous parsing (5.9 and later)

To separate document crawling from document parsing, enable Tika Asynchronous Parsing on remote V2 connectors.

Connector compatibility

Whenever you upgrade Fusion, you must also update your remote connectors to match the new version of Fusion.

Firewall configuration best practices

You can use a forward proxy server to allow HTTP/2 communication into the Fusion cloud. A forward proxy server acts as an intermediary between the firewalled connector and Fusion and will only allow specified communication traffic and block unauthorized traffic.

Asynchronous parsing

This feature is available in Fusion 5.9 and later.

To separate document crawling from document parsing, use Tika Asynchronous parsing on remote V2 connectors.

Use Tika Asynchronous Parsing

This document describes how to set up your application to use Tika asynchronous parsing.Unlike synchronous Tika parsing, which uses a parser stage, asynchronous Tika parsing is configured in the datasource and index pipeline. For more information, see Asynchronous Tika Parsing.

Field names change with asynchronous Tika parsing.In contrast to synchronous parsing, asynchronous Tika parsing prepends parser_ to fields added to a document. System fields, which start with \_lw_, are not prepended with parser_. If you are migrating to asynchronous Tika parsing, and your search application configuration relies on specific field names, update your search application to use the new fields.

Configure the connectors datasource

Navigate to your datasource.
Enable the Advanced view.
Enable the Async Parsing option.
Fusion 5.9.11 and later uses your parser configuration when using asynchronous parsing.The asynchronous parsing service performs Tika parsing using Apache Tika Server. In Fusion 5.8 through 5.9.10, other parsers, such as HTML and JSON, are not supported by the asynchronous parsing service. By enabling asynchronous parsing, the parser configuration linked to your datasource is ignored. In Fusion 5.9.11 and later, other parsers, such as HTML and JSON, are supported by the asynchronous parsing service. By enabling asynchronous parsing, the parser configuration linked to your datasource is used.
Save the datasource configuration.

Configure the parser stage

You must do this step in Fusion 5.9.11 and later.

Navigate to Parsers.
Select the parser, or create a new parser.
From the Add a parser stage menu, select Apache Tika Container Parser.
(Optional) Enter a label for this stage. This label changes the names from Apache Tika Container Parser to the value you enter in this field.
If the Apache Tika Container Parser stage is not already the first stage, drag and drop the stage to the top of the stage list so it is the first stage that runs.

Configure the index pipeline

Go to the Index Pipeline screen.
Add the Solr Partial Update Indexer stage.
Turn off the Reject Update if Solr Document is not Present option and turn on the Process All Pipeline Doc Fields option:
Include an extra update field in the stage configuration using any update type and field name. In this example, an incremental field docs_counter_i with an increment value of 1 is added:
Enable the Allow reserved fields option:
Click Save.
Turn off or remove the Solr Indexer stage, and move the Solr Partial Update Indexer stage to be the last stage in the pipeline.

Asynchronous Tika parsing setup is now complete. Run the datasource indexing job and monitor the results.

Fusion Connectors

​Prerequisites

​Connector compatibility

​System requirements

​Enable backend ingress

​Connector configuration example

​Minimal example

​Logback XML configuration file example

​Run the remote connector

​Test communication

​Encryption

​Egress and proxy server configuration

​Password encryption

​Connector restart (5.7 and earlier)

​Recoverable bridge (5.8 and later)

​Job expiration duration (5.9.5 only)

​Use the remote connector

​Enable asynchronous parsing (5.9 and later)

​Connector compatibility

​Firewall configuration best practices

​Asynchronous parsing

​Configure the connectors datasource

​Configure the parser stage

​Configure the index pipeline

Prerequisites

Connector compatibility

System requirements

Enable backend ingress

Connector configuration example

Minimal example

Logback XML configuration file example

Run the remote connector

Test communication

Encryption

Egress and proxy server configuration

Password encryption

Connector restart (5.7 and earlier)

Recoverable bridge (5.8 and later)

Job expiration duration (5.9.5 only)

Use the remote connector

Enable asynchronous parsing (5.9 and later)

Connector compatibility

Firewall configuration best practices

Asynchronous parsing

Configure the connectors datasource

Configure the parser stage

Configure the index pipeline