You can configure dual management ports to form LAG with both ports as active. Active-standby, also called active-backup, is supported for LAG on management ports. The management interfaces form a LAG, and only one of the members is active at anytime. The other link is in standby mode, and joins the LAG only if the primary link is down. When the primary link comes up, it joins the LAG and the backup link unjoins.
Use the switch-setup-modify command option for the parameter, mgmt-lag, active-standby.