Any NetWare cluster to be converted must be running at least NetWare 6.0. If you have a NetWare 5.1 cluster, you must upgrade to a NetWare 6.5 cluster before adding new OES cluster nodes or converting existing NetWare cluster nodes to OES cluster nodes. The process for converting 6.0 and 6.5 nodes is the same.
Each OES server must contain at least one local disk device.
At least 512 MB of memory must be available on each server in the cluster.
While identical hardware for each cluster server is not required, having servers with the same or similar processors and memory can reduce differences in performance between cluster nodes.
All nodes in a given cluster, whether NetWare or OES:
Must be configured with a static IP address.
An additional IP address needs to be available for the cluster and for each cluster resource and cluster-enabled pool.
Must reside on the same IP subnet and in the same eDirectory tree.
A shared disk subsystem should be connected to all servers in the cluster (optional, but recommended for most configurations) and should be properly set up and functional according to the manufacturer's instructions.
We recommend configuring the disks contained in the shared disk system to use mirroring or RAID to add fault tolerance to the shared disk system.
At least 20 MB of free disk space on the shared disk system needs to be available for creating a cluster partition.
The Novell Cluster Services installation automatically allocates one cylinder on one drive of the shared disk system for the cluster partition. Depending on the location of the cylinder, the actual amount of space used by the cluster partition might be less than 20 MB.
High-speed Fibre Channel cards, cables, and switch or SCSI cards and cables need to be installed to connect the servers to the shared disk subsystem.
If you are using a fibre channel SAN, the host bus adapters (HBAs) for each cluster node should be identical.
If you are using iSCSI for shared disk system access, make sure you have configured iSCSI initiators and targets prior to installing Novell Cluster Services.
Novell Cluster Services software must be running on the OES server (SLES 11 and OES must be installed on every OES server added to a cluster). You can install Novell Cluster Services and create a new cluster, or add a server to an existing cluster either during the SLES 11/OES installation or afterwards, using YaST.
See Installing Novell Cluster Services during an OES Installation
and Installing Novell Cluster Services on an Existing OES Server
in the OES 2015 SP1: Novell Cluster Services for Linux Administration Guide."