To upgrade NSS volumes from NetWare 5.1 to NetWare 6.x, simply mount the NSS volume on your NetWare 6.x server. The mounting process starts the upgrade. The upgrade takes some time. You must leave the upgraded NSS volume mounted on NetWare 6.x afterwards; the media format is not backwards compatible with your NetWare 5.1 server.
Use Volume Copy Upgrade to upgrade legacy NetWare 5.1 Traditional volumes to NSS volumes on OES NetWare. For information, see Upgrading Legacy NSS and NetWare Traditional Volumes.
You can mount NSS volumes that have not been upgraded to the new format directly on OES 2 Linux and OES 1 Linux servers. You can mount NSS volumes from NetWare 6.0 servers directly onto OES 2 Linux and later. For information, see the following:
NetWare 6.5 SP3, OES 1 SP2 Linux, and earlier servers do not support the new media format for NSS. For information, see Section 4.1, Guidelines for Upgrading the Media Format of NSS Volumes.