In this scenario, both the NetWare server and the OES server are in the same eDirectory tree. The NetWare source server must be running NetWare 5.1 SP8 or later versions. The Linux target server must be running OES 2015 SP1 on 64-bit hardware.
Use iManager to move the DNS server from a NetWare NCP server to an OES NCP server. For information see Using Java Console to Migrate Servers within the Same eDirectory Tree
in the OES 2018 SP2: Migration Tool Administration Guide.