When trying to apply the activation key for Control Hub On-Pre from the CLI, one might receive an error:
ERROR: java.io.IOException: java.security.SignatureException: Signature length not correct: got 512 but was expecting 256
Control Hub is unable to read or reach the streamset-activation.jar file in the lib directory.
Under the $DPM_HOME/apps/security/lib, check to see if there is both a 'streamsets-activation-<version>.jar' and a 'streamsets-activation-dev-<version>.jar'.
If there is a 'streamsets-activation-dev-<version>.jar', remove the dev jar, as it is meant only for the dev builds.
If there is no jar in the directory, a user may have deleted the file or was absent from the installation process. To retrieve a new jar file, extract the jar file from a tarball of the Control Hub On-Prem version that one is using.