---
layout: doc_page
title: "Realtime Process"
---

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Older versions of Apache Druid supported a standalone 'Realtime' process to query and index 'stream pull'
modes of real-time ingestion. These processes would periodically build segments for the data they had collected over
some span of time and then set up hand-off to [Historical](../design/historical.md) servers.

This processes could be invoked by

```
org.apache.druid.cli.Main server realtime
```

This model of stream pull ingestion was deprecated for a number of both operational and architectural reasons, and
removed completely in Druid 0.16.0. Operationally, realtime nodes were difficult to configure, deploy, and scale because
each node required an unique configuration. The design of the stream pull ingestion system for realtime nodes also
suffered from limitations which made it not possible to achieve exactly once ingestion.

The extensions `druid-kafka-eight`, `druid-kafka-eight-simpleConsumer`, `druid-rabbitmq`, and `druid-rocketmq` were also
removed at this time, since they were built to operate on the realtime nodes.

Please consider using the [Kafka Indexing Service](../development/extensions-core/kafka-ingestion.md) or
[Kinesis Indexing Service](../development/extensions-core/kinesis-ingestion.md) for stream pull ingestion instead.