I executed the following command via RMAN:
run {
allocate auxiliary channel ch4 device type 'SBT' parms='SBT_LIBRARY=/usr/openv/netbackup/bin/libobk.so64.1 ENV=(NB_ORA_CLIENT= server01-nbu, NB_ORA_SERVER=nbumaster,NB_ORA_CLASS=ORA_RMAN_SERVER01_5WK)'...
