KB-1467 Transaction logs FAQ

Table of Contents:

Where is the transaction log located?

Kafka and Zookeeper each have a directory where they write their data files (by default Kafka's data is in <APPIAN_HOME>/services/data/kafka-logs and Zookeeper's data is in <APPIAN_HOME>/services/data/zookeeper). These files store data for the Appian environment. Touching these files beyond documented procedures may result in data loss or the environment being in an unsupported state.

How many files are there and do I have to manually clean it up?

The number of files will vary. Kafka and Zookeeper will automatically clean up (delete) older files which they no longer need. Appian automatically removes transactions from Kafka once they are older than the third most recent checkpoint for the relevant engine.

Is the cleanup process configurable?

How frequently Kafka and Zookeeper data is cleaned up is configurable based on how frequently the engines checkpoint. The more frequently the engines checkpoint, the less data will be kept in the transaction logs. Refer to Configuring Application Checkpointing for more information.

Would checkpointing more frequently influence the maintenance process of the transaction log?

By default, old checkpoints do not get deleted. They are moved to an archive location (<APPIAN_HOME>/services/data/archived). Checkpointing more frequently will use up more disk space for the checkpoint images. The CleanupArchives Script should be used to clean up these old checkpoint images.

Affected Versions

This article applies to Appian 17.3 and later.

Last Reviewed: January 2018