You can move devices containing NSS volumes from NetWare to OES server by decommissioning the volumes on the device in the eDirectory, then recommissioning the volumes on the new server. For more information, see the Moving Non-Clustered Devices From NetWare 6.5 SP8 Servers to OES 2018 SP2
in the OES 2018 SP3: NSS File System Administration Guide for Linux.
For shared NSS pools and volumes, OES Cluster Services provides this service automatically during a rolling cluster conversion from NetWare to OES. For information about converting shared pool cluster resources and service resources, see the OES 2015 SP1: Novell Cluster Services NetWare to Linux Conversion Guide.