KB-2240 Appian Data Server fails to start with "Failed to create election service (Raft)" error in the hs-gateway.log file

Symptoms

• Appian Data Server (ADS) fails to start with the following error in watchdog.log:
  

  "level":"ERROR","time":"*","logger":"watchdog","caller":"HistoricalStoreStarter.java:80","thread":"process-starter-1","msg":"Failed to start HS gateway (port=5401)"

• The following error is observed in the hs-gateway.log:
  

  "level":"FATAL","time":"*","logger":"hs-gateway","caller":"hs/main.go:137","msg":"Failed to create election service (Raft)","pid":*,"hostname":"*.*.*.*","error":"the required entries are not present in the raft log: to fix this issue, delete the election directory (located at <ADS_HOME>/data-server/node/election) on ALL NODES in the cluster and then restart ADS" 

Cause

This may happen if ADS data is modified or incorrectly copied in any way during an upgrade, or when converting a standalone environment to a high availability setup.

Action

Follow the actions suggested in the hs-gateway.log:

1. Delete the election directory (located at <ADS_HOME>/data-server/node/election) on ALL NODES in the cluster.
2. Restart ADS on all nodes in the cluster.

Affected Versions

This article applies to Appian 18.1 and later.

Last Reviewed: May 2023