15.1 Requirements for Using CSM Cluster Resources

On OES 1 and OES 2 clusters, a cluster resource for a shared Linux POSIX volume used the Enterprise Volume Management System (EVMS) utility to add a Cluster Segment Manager (CSM) on the device. Because EVMS is deprecated in SUSE Linux Enterprise Server 11, it is not available in OES 11 and later (OES 11x).

Novell Cluster Services on OES 11x provides compatibility support for these CSM-based cluster resources. It has been modified in the following ways to allow you to move clustered Linux POSIX file systems from OES 2 SP3 nodes to OES 11x nodes in a mixed-mode cluster, and use them after upgrading the cluster:

  • Recognizes and supports the EVMS-based file system structure.

  • Provides a way for managing a resource in the load, unload, and monitor scripts on OES 11x clusters that works with its existing EVMS device and segment structure.

  • Changes the device path from /dev/evms/ to /dev/mapper/, which is the same location where LVM devices are stored.

The Cluster Segment Manager Import/Export (CSMPORT, csmport) utility provides script commands that make it possible to use the CSM resources. The commands activate, deactivate, or check the status of the CSM container. You must add csmport commands in resource’s the load script, unload script, and monitor script before you bring the resource online on OES 11x servers during a cluster upgrade. For information about the utility commands that are used in the scripts, see Section A.6, CSMPORT Utility (Cluster Segment Manager Import/Export), or see the csmport(8) man page.

A mixed-mode cluster is supported as a temporary configuration scenario for converting an OES 2 SP3 cluster to an OES 11x cluster. After the CSM-based resource is configured to run in compatibility mode on OES 11x , it should fail over only to the OES 11x nodes in the mixed-mode cluster. See Section 8.1.3, Linux POSIX File Systems on an EVMS CSM (Compatibility Only).

You cannot create new CSM-based cluster resources on OES 11x clusters. For new Linux POSIX volume resources, you must use the Linux Logical Volume Manager (LVM) volume groups as described in Section 14.0, Configuring and Managing Cluster Resources for Shared LVM Volume Groups.