Overview

In the default state, all Snaplex nodes can accept new Pipeline execution requests with Pipeline runs load balanced automatically across the nodes. The other state is Maintenance Mode. State transitions occur before and after the default Snaplex states.

Snaplex State Transition

A state transition can occur for many reasons–because of a Snaplex version update, a configuration change to the Snaplex, or a restart. When a state transition is required for a Snaplex, one node (or more for larger Snaplex instances) at a time enters a Cooldown state, in which new Pipeline execution requests should not be not sent to the node. In this state, the node waits for currently running Pipelines to complete. For long-running Pipelines that are set up to poll continuously (like a Pipeline using File Poller or JMS Consumer Snaps) and Ultra Pipelines, the Pipeline is sent a state notification to allow the Pipeline to stop polling for new records.

Pipeline Execution Timeout when Restarting a Snaplex

A Snaplex has a configurable timeout (the default is 15 minutes), called the Restart Max Wait Time, which you can set in the Snaplex Settings tab in the Update Snaplex and Create Snaplex dialogs. If all Pipelines complete within this timeout, then the node transitions to the required state. If Pipelines are still running after this timeout, then those Pipelines terminate to allow the transition to the required state.

You can increase the default value of 15 minutes to a higher value on Snaplex instances that run longer-running Pipelines (in terms of duration). However, for polling and Ultra Pipelines, you do not have to increase this value since the Pipeline is notified to stop polling for new records, thus allowing the Pipeline to terminate cleanly.

Snaplex Version Change

When a Snaplex version change is initiated, one node at a time undergoes a transition of its state. After the node enters the Cooldown state and running Pipelines complete, the JCC process on the node terminates and restarts with the new version of the Snaplex binaries.
 Since the Snaplex version upgrade happens in a rolling manner with no downtime required on Pipeline executions, your interaction is not required during the rolling restart—all node transitions are completed automatically.

Snaplex Maintenance Mode


When you place a Snaplex node in maintenance mode, the node enters the Cooldown state and waits for running Pipelines to complete. After all Pipeline runs come to completion, the node enters maintenance mode, during which the node does not accept any Pipeline execution requests.

During an upgrade, the behavior of the Snaplex depends on the type:

Cloudplex: If a node is in maintenance mode and the Snaplex version is updated, the Cloudplex exits maintenance mode after the version update.

Groundplex: If a node is in maintenance mode and the Snaplex version is updated, the Groundplex remains in maintenance mode after the update.