The controller is not available at localhost:9990

[Flyslinger2]

[root@localhost opt]# /opt/wildfly/bin/jboss-cli.sh --connect '/subsystem=elytron/credential-store=defaultCS:add(location=keystore/credentials, relative-to=jboss.server.config.dir, credential-reference={clear-text="{EXT}/usr/bin/wildfly_pass", type="COMMAND"}, create=true)'

Failed to connect to the controller: The controller is not available at localhost:9990: java.net.ConnectException: WFLYPRT0053: Could not connect to remote+http://localhost:9990. The connection failed: WFLYPRT0053: Could not connect to remote+http://localhost:9990. The connection failed: Connection refused

[primetomas]

"java.net.ConnectException" means it can't eatablish a network connection. You may have missed to configure remoting on your WildFly server. Check the documentation. Also check the WildFly server log to see that it has started correctly. It may have been some error with an earlier command that caused it to go down.