The variable bwlimit used to be acceptable but was deprecated in Vertica 7.1 and finally removed in Vertica 9.0. CAPM 3.6 uses Vertica Analytic Database 9.0.1-7.
Resolution
Edit the ini file being used for either backup or copycluster and remove the following line from the Transmission section:
<Please see attached file for image>
Additional Information
Vertica documentation reference for the removal of the bwlimit variable.