Typically, the primary purpose of a cluster is to provide file and print services. Make sure you check the volume resources because it is easy to overload these services. As a general guideline, Novell recommends that NSS volume resources be kept at a total capacity of 80% or less. If you need to reduce the number of standalone servers in production, the logical approach is to move data and transfer services into the high availability resources of a cluster.
Review the health of NCS background operations to resolve any operational issues with the cluster.
Make sure all cluster nodes are up to the latest support pack levels.
Avoid spanning LUNs across NSS pools
Where necessary, review and modify the cluster design to take full advantage of the High Availability capabilities of current release software.
Novell recommends the following steps to address both the reliability and the performance of your current cluster:
Make sure all NetWare nodes are at NetWare 6.5 SP7 or later
Use relatively small LUNs and data volumes
Introduce OES 11 nodes as required
Reconfigure the SAN to host DST shadow volumes
There are a two paths for moving existing NetWare clusters to OES: converting the existing clusters (also referred to as a rolling cluster conversion) or using a parallel build.
Cluster Conversion (Same Cluster). In order to convert existing clusters, new OES 11 servers need to be built with the same LUN visibility as the existing NetWare nodes and the new servers added to the existing cluster. The new OES nodes then mount the existing volumes and services, and the NetWare servers are removed from the cluster and removed from eDirectory. Although it is feasible to use a mixed NetWare and OES cluster temporarily as an upgrade strategy, Novell does not recommend it as a permanent production implementation.
Parallel Build (New Cluster). A parallel-build OES upgrade strategy entails building a new separate OES 11 cluster on the same SAN as the existing NetWare clusters. Doing so allows resources to be moved to the new cluster by changing LUN visibility from the old cluster nodes to the new. This can also be done in a phased approach. After the last resource is moved, the NetWare cluster can be removed from the tree. Because it is a new cluster, the virtual server names will change and login scripts and other references will need to be updated during the upgrade process.
There are pros and cons to each approach so you need to do a more detailed analysis and have assistance from Novell Consulting before upgrading a cluster.
Novell Cluster Services software must be running on the OES server (SLES 11 and OES 11 must be installed on every server you want to add 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 11 SP3: Novell Cluster Services for Linux Administration Guide.
Refer to the following sections in the OES 11 SP3: Novell Cluster Services for Linux Administration Guide for additional information about transferring Novell Cluster Services to OES: