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title: Nebula Engine sidebar_position: 17

This article mainly introduces the installation, use and configuration of the Nebula engine plugin in Linkis.

1. Pre-work

1.1 Engine installation

If you want to use Nebula engine on your Linkis service, you need to install Nebula service and make sure the service is available.

1.2 Service Verification

# Execute the task
./usr/local/bin/nebula-console -u root -p password --address=graphd --port=9669

CREATE SPACE IF NOT EXISTS my_space_1 (vid_type=FIXED_STRING(30));SHOW SPACES;

# Get the following output to indicate that the service is available
+--------------+
| Name         |
+--------------+
| "my_space_1" |
+--------------+

2. Engine plugin deployment

2.1 Engine plugin preparationnon-default engine

Compile the engine plug-in separately (requires maven environment)

# compile
cd ${linkis_code_dir}/linkis-engineconn-plugins/nebula/
mvn clean install
# The compiled engine plug-in package is located in the following directory
${linkis_code_dir}/linkis-engineconn-plugins/nebula/target/out/

EngineConnPlugin Engine Plugin Installation

2.2 Upload and load engine plugins

Upload the engine package in 2.1 to the engine directory of the server

${LINKIS_HOME}/lib/linkis-engineplugins

The directory structure after uploading is as follows

linkis-engineconn-plugins/
├── nebula
│   ├── dist
│   │   └── 3.0.0
│   │       ├── conf
│   │       └── lib
│   └── plugin
│       └── 3.0.0

2.3 Engine refresh

2.3.1 Restart and refresh

Refresh the engine by restarting the linkis-cg-linkismanager service

cd ${LINKIS_HOME}/sbin
sh linkis-daemon.sh restart cg-linkismanager

2.3.2 Check whether the engine is refreshed successfully

You can check whether the last_update_time of the linkis_engine_conn_plugin_bml_resources table in the database is the time to trigger the refresh.

#login to `linkis` database
select * from linkis_cg_engine_conn_plugin_bml_resources;

3 Engine usage

3.1 Submit tasks through Linkis-cli

sh ./bin/linkis-cli  -engineType nebula-3.0.0 -codeType nebula \
 -code 'CREATE SPACE IF NOT EXISTS my_space_1 (vid_type=FIXED_STRING(30));SHOW SPACES;' \
 -runtimeMap linkis.nebula.port=9669  -runtimeMap linkis.nebula.host=wds07

More Linkis-Cli command parameter reference: Linkis-Cli usage

4. Engine configuration instructions

4.1 Default Configuration Description

Configuration	Default	Required	Description
linkis.nebula.host	127.0.0.1	no	host
linkis.nebula.port	9669	no	port
linkis.nebula.username	root	no	username
linkis.nebula.password	nebula	no	password
linkis.nebula.max.conn.size	100	no	max conn size
linkis.nebula.reconnect.enabled	false	no	whether to retry after the connection is disconnected
linkis.engineconn.concurrent.limit	100	no	Maximum concurrent number of engines
linkis.nebula.default.limit	5000	no	Limit the number of result sets