Administering the Data Access Gateway
The HPE Ezmeral Data Fabric Data Access Gateway is a service that acts as a proxy and gateway for translating requests between lightweight client applications and the HPE Ezmeral Data Fabric cluster. This section describes considerations when upgrading the service, how to modify configuration settings, and how to administer and manage the service.
Installing the Data Access Gateway Service
The HPE Ezmeral Data Fabric Data Access Gateway is installed when you install the HPE Ezmeral Data Fabric Database using the HPE Ezmeral Data Fabric Installer. To manually install the service, see Installing Data Access Gateway. For conceptual information, see Understanding the HPE Ezmeral Data Fabric Data Access Gateway.
Shutting Down and Upgrading the Data Access Gateway Service
When the Data Access Gateway receives a shutdown request, it stops accepting new requests and returns an error to the client. Any in-progress requests are allowed to complete before shutting down the service. This allows you to perform rolling upgrades.
Modifying Configuration Settings for the Data Access Gateway Service
Logging Properties
The HPE Ezmeral Data Fabric Data
Access Gateway uses standard Log4J configuration to control its logging. The log4j
properties are in the /opt/mapr/data-access-gateway/conf/log4j2.xml
file
on nodes where you have installed the service. After modifying any properties on a node,
restart the service. For details, see Administering the Data Access Gateway Service.
Log data is stored in the
/opt/mapr/data-access-gateway/logs/data-access-gateway.log
file.
To configure HPE Ezmeral Data Fabric Data
Access Gateway properties, modify
/opt/mapr/data-access-gateway/conf/properties.cfg
on nodes where you
have installed the service.
- auth.token.expiration
- Default: 1800 seconds
- grpc.service.max-message-size
- Default: 32MB
- grpc.service.ojai.query.result-limit
- Default: 5000
- grpc.service.port
- Default: 5678
- grpc.service.ssl.enabled
- Default: cluster
- rest.https.port
- Default:8243
- rest.result.limit
- Default:5000
There is also a configuration file
/opt/mapr/data-access-gateway/conf/ojai-config.json
for parameters
used by Data Access Gateway clients:
- HPE Ezmeral Data Fabric Database JSON REST API
- Node.js OJAI
- Python OJAI
- C# OJAI
- Go OJAI
- Java OJAI Thin Client
A parameter you can modify is the client sort limit:
{ "ojai": { "mapr": { "query": { "max-client-sort-limit": 6000 } } } }
To understand why you might want to modify this parameter, see Comparisons and Sorts in OJAI Queries.
After modifying any parameters on a node, restart the service as described in Administering the Data Access Gateway Service.
The Warden configuration for the HPE Ezmeral Data Fabric Data
Access Gateway is in the
/opt/mapr/data-access-gateway/conf/warden.data-access-gateway.conf
file on nodes where you have installed the Data Access Gateway. To control the amount of
memory allocated to the service, modify the following settings:
- service.heapsize.max
- Default:3000
- service.heapsize.min
- Default:3000
After modifying the warden configuration file on a node, run configure.sh -R
, and restart the
service:
/opt/mapr/server/configure.sh -R
maprcli node services -nodes <node name> -name data-access-gateway -action restart
Administering the Data Access Gateway Service
The HPE Ezmeral Data Fabric Data
Access Gateway is a service that you administer in the same manner as other HPE Ezmeral Data Fabric services. The
name of the service is data-access-gateway
.
maprcli node services -nodes <node name> -name data-access-gateway -action restart
For details about other operations you can perform on the service, see Managing Services.