KB-2172 "System call filters failed to install" error during search server startup


The search server fails to start up when start.sh (start.bat on Windows) is run and the following error is logged to the console:

bootstrap checks failed
system call filters failed to install; check the logs and fix your configuration or disable system call filters at your own risk


Starting in 20.4, the search server runs bootstrap checks to validate the security and configuration of the host machine before starting up. On machines running CentOS 6, these bootstrap checks inherently fail due to limitations of the OS.


After confirming that the machine is running CentOS 6, follow these steps to disable the bootstrap checks:

  1. Create a new file named elasticsearch.yml in <APPIAN_HOME>/search-server/conf/ with the following contents: bootstrap.system_call_filter: false
  2. Start the search server.

Note: For HA deployments of the search server, this file must be created in the appropriate directory on each instance of the search server. When upgrading Appian, this configuration must be copied over to its correct location as well.

Affected Versions

This article applies to Appian 20.4 and later.

Last Reviewed: February 2021