3.6 Caveats for Deploying NSS AD

Be aware of the following caveats before installing and configuring NSS AD.

3.6.1 Clustered Node Issue

Pre-OES 2015 servers cannot mount NSS-AD media-upgraded pools.

  1. If possible, you should upgrade all cluster nodes to OES 2015 or later as part of your NSS-AD deployment.

  2. If you cannot upgrade your cluster nodes at the same time, ensure the following:

    A mixed node cluster environment can contain OES 11 SP2, OES 2015, OES 2015 SP1, OES 2018, OES 2018 SP1, and OES 2018 SP2 nodes. The AD media upgraded NSS32 and NSS64 pools cannot be loaded in OES 11 SP2 nodes.

    When a resource comes online, it tries to load on a node based on the preferred node assignment (OES 2015 or later nodes), and the older OES cluster nodes are skipped from the preferred node list. If OES 2015 or later nodes are not available in the cluster, the resources are moved to “unassigned” state.

    However, if the upgraded (OES 2015 or later) node comes up or any new OES (OES 2015 or later) node is added to the cluster, the resource will automatically loads on the OES 2015 or later node.

    IMPORTANT:

    • All nodes in the cluster must be patched with the latest OES patches. Otherwise, the AD media resource goes to comatose state on nodes earlier than OES 2015.

    • All nodes in the cluster must belong to OES 11 SP2 or later. If any OES node in the cluster is older than OES 11 SP2, this feature does not work.

    For more information, see Configuring Preferred Nodes and Node Failover Order for a Resource in the OES 2018 SP3: OES Cluster Services for Linux Administration Guide.

3.6.2 Recommendations During Upgrade

When upgrading the OES server, if NSS AD pattern is selected, then any misconfiguration in joining the domain can result in upgrade failure. Hence, it is recommended not to install NSS AD Support as part of the upgrade process. Instead, you must do the following:

  1. Complete the upgrade/migration processes as documented in Upgrading to OES 2018 SP3 in the OES 2018 SP3: Installation Guide

  2. Ensure that all of the NSS AD Infrastructure Requirements are met.

  3. Run the YaST OES Installation module (or the NSS AD Support module) on the OES server and complete the applicable instructions in Section 4.0, Installing and Configuring NSS AD Support.

For information on planning a migration to OES 2018 SP2, see the OES 2018 SP3: Migration Tool Administration Guide.