5.1 Guidelines for Upgrading the Media Format of NSS Volumes

5.1.1 Cross-Platform Support for the NSS Media Upgrade

The NSS media upgrade for enhanced hard links support is available for the following operating platforms (and later versions):

  • Novell Open Enterprise Server 11

  • Novell Open Enterprise Server 2 Linux and NetWare

  • Novell Open Enterprise Server 1 SP2 NetWare

  • NetWare 6.5 SP4

If the NSS volume is used in a cluster with OES Cluster Services, all nodes in the cluster must be upgraded to a supported platform before you upgrade the media format for any shared volumes. After you upgrade the media format on an NSS volume, it cannot be mounted on an unsupported platform.

5.1.2 Which NSS Volumes to Upgrade

With a few exceptions as noted below, it is highly recommended that you upgrade the NSS volume to the new metadata structure after you upgrade the operating system to a supported platform.

Do not upgrade the media format of the NSS volume to the new metadata structure if any of the following conditions exist:

  • You have not yet verified that your system is performing as expected after upgrading the operating system, and you might need to roll back to an earlier release.

  • You plan to migrate one or more devices containing the NSS volume to an unsupported platform.

  • You need to share this volume with a mixed cluster with OES Cluster Services where there are some unsupported platforms in the mix. The cluster software prevents the media upgrade unless all operating systems in the cluster support the new media format.

5.1.3 Before Upgrading the Media Format

Opportunity to Roll Back Before the Media Upgrade

When you upgrade the operating system, NSS does not automatically upgrade the media format to use the new metadata structure. This allows you to the opportunity to roll back to the previous release if necessary. Before you upgrade the media format of NSS volumes to the new data structure, make sure the server is performing as expected.

WARNING:After the media format is upgraded to the new metadata structure, you cannot roll back to a previous release.

Hard Link Behavior without a Media Upgrade

Until you upgrade the media format for enhanced hard link support, any existing hard links on the NSS volume are visible, and they can be opened, closed, read, and written. However, you cannot create new hard links, and you cannot rename or delete existing hard links. Attempts to do so are rejected with an error.

Clusters and the Media Upgrade

If you attempt to upgrade the media format for a shared NSS volume on a cluster with OES Cluster Services, the upgrade is refused until all servers on the system are configured with a supported operating system. Make sure to upgrade all cluster nodes to a supported platform before attempting to upgrade the shared volume.

5.1.4 After Upgrading the Media Format

After you upgrade the volume to use the media format with enhanced hard links, the following constraints apply for its use:

  • The Hard Links attribute must be enabled for the upgraded NSS volume before you can create hard links.

    When you upgrade the NSS volume to use the new media format, if any old-style hard links are detected, the Hard Links attribute is automatically enabled. Otherwise, the volume is upgraded, but the attribute is disabled and must be enabled before you can create hard links. For information, see Section 25.3, Enabling or Disabling the Hard Links Attribute.

  • The upgraded NSS volume cannot be rolled back to use the old media format.

  • You cannot roll back the operating system to a previous version.

  • You cannot migrate a device containing the upgraded volume to a system with an unsupported operating system.

  • Only nodes that have a supported operating system can be added to a cluster where shared volumes use the upgraded media format.

5.1.5 If You Do Not Upgrade the Media Format

If you do not upgrade the media format for an NSS volume, the volume’s format uses the same metadata structure as is used on earlier releases. Any existing hard links on your system’s NSS volumes are visible, and they can be opened, closed, read, and written. However, until you upgrade the NSS volume to the new structure, you cannot create new hard links, and you cannot rename or delete existing hard links. Attempts to do so are rejected with an error.

If the non-upgraded NSS volume is shared in a mixed cluster with OES Cluster Services, hard links can be created, renamed, or deleted by first mounting the volume on a node in the cluster with an operating system that is compatible with the old media format.

It is possible to move devices that contain non-upgraded NSS volumes cross-platform to servers with operating systems compatible with the old media format. For information about moving media cross-platform, see Section 12.2, Moving Non-Clustered Devices From NetWare 6.5 SP8 Servers to OES 2018 SP2.