8.1 Requirements for Creating LVM Cluster Resources

Your system must meet the requirements in this section in addition to the cluster requirements described in Planning for Novell Cluster Services in the OES 11 SP2: Novell Cluster Services for Linux Administration Guide.

8.1.1 Novell Cluster Services

Novell Cluster Services must be installed, configured, and running when you create and manage the shared LVM volume group and logical volume. The cluster must be active.

8.1.2 Linux Logical Volume Manager 2 (LVM2)

The Linux Logical Volume Manager (LVM) 2 software supports LVM volume groups and logical volumes. LVM2 must be installed and running on each node in the cluster. LVM2 runs automatically on OES 11 and later servers; no separate installation or setup is required.

8.1.3 Clustered Logical Volume Manager Daemon (CLVMD)

The Linux Clustered Volume Manager Daemon (CLVMD, clvmd) software allows you to exclusively mount a shared LVM volume group on one node at a time in a cluster. It distributes the LVM metadata updates around a cluster. CLVM must be installed and running on each node in the cluster. CLVMD runs automatically on OES 11 and later servers; no separate installation or setup is required.

IMPORTANT:Ensure that you have installed the latest patches for SUSE Linux Enterprise Server 11 SP1 and later. Clustered LVM volume groups require Linux kernel version 2.6.32.45-0.3 or later.

CLVM requires that shared LUNs that you use for clustered LVM devices be allocated to every node in the cluster. It is not supported to allocate a shared LUN to only selected nodes in the cluster.

8.1.4 Resource IP Address

Each cluster resource requires a unique static IP address that is in the same subnet as the IP addresses that are used for the cluster and cluster nodes. The IP address is used to provide access and failover capability for the cluster-enabled volume.

8.1.5 Shared Storage Devices

The shared SAN storage device that you use for an LVM volume group cluster resource must be initialized and have no partitions on it. When the device is used in a cluster resource, LVM uses the entire device for the volume group. Ensure that you size your LUNs accordingly. Use the SAN management tools to assign the LUN to all nodes in the cluster.

IMPORTANT:If you use NSS management tools to manage devices, do not enable the Shareable for Clustering option. Doing so adds a 4 KB partition to the device, which makes it unavailable to LVM.

8.1.6 All Nodes Must Be Present

LVM requires the presence of all the nodes in the cluster to modify the metadata on shared storage. This allows LVM to get the exclusive locks it needs to perform actions on shared storage.

Before you attempt to create or modify LVM volume group cluster resources:

  • All of the nodes must be joined in the cluster and running properly.

  • The clvmd daemon must be running on all nodes.

8.1.7 Working in Mixed Node OES Clusters

LVM volume group cluster resources are not supported in mixed-node OES clusters when you upgrade from OES 2 SP3 to OES 11 (or later). Complete the upgrade before you create new cluster resources.

8.1.8 NCP File Access with Novell NCP Server

Novell NCP Server can be used to provide NCP file access to Linux POSIX file systems on OES 11 and later servers. Its NCP volumes feature can be used to provide NCP access to files on an LVM volume group cluster resource. NCP Server must be installed, configured, and running on each node in the cluster.

Naming Conventions for NCP Volumes

NCP volume names can be up to 14 alphanumeric characters, using uppercase letters A through Z and numbers 0 through 9. Underscores (_) are allowed.

If you NCP enable a Linux volume as you create it with NSSMU or the nlvm create linux volume command, the NCP volume name uses the specified Linux volume name, but all letters are capitalized. NCP treats the Linux volume name as case insensitive. Ensure that the specified Linux volume name does not exceed 14 characters, does not use special characters, and is unique across all nodes in the cluster for both Linux and NCP.

Creating an NCP Volume for a New Clustered LVM Volume

You can configure NCP file access for an LVM volume group cluster resource when you create the resource by using NSSMU or the nlvm create linux volume command. With the NCP option enabled, these tools automatically add commands to the resource scripts that mount, dismount, and monitor an NCP volume. The NCP volume is named the same as the LVM logical volume name, and all letters in the name are capitalized. The tools automatically create an NCP Virtual Server object for the volume group cluster resource.

Creating an NCP Volume on an Existing Clustered LVM Volume

You can create an NCP Virtual Server object for the LVM cluster resource to make the resource visible in the eDirectory tree. The virtual server alone does not provide NCP file access.

You can add NCP file access support to an existing LVM cluster resource:

  1. Create an NCP Virtual Server object for the LVM cluster resource.

  2. Create the NCP volume at the mount point path for the Linux volume. You can also create shares at subdirectories on the volume. This creates an NCP Volume object.

  3. Modify the NCP configuration file to comment out the instance for the NCP volume. This allows the LVM cluster resource to control mounts and dismounts for the NCP volume.

  4. Modify the LVM cluster resource scripts to add commands that define, mount, dismount, and monitor the NCP volume.

  5. Take the resource offline, then bring it online to apply the changes.

For details about setting up NCP volumes on an existing clustered Linux volume, see Configuring NCP Volumes with Novell Cluster Services in the OES 11 SP2: NCP Server for Linux Administration Guide.

Using Antivirus Software with NCP Volumes

For information about using antivirus software with NCP volumes, see McAfee Antivirus Requires Additional Configuration in the OES 11 SP2: Planning and Implementation Guide.

8.1.9 SMB/CIFS File Access with Novell Samba

Samba is an open source software suite that lets Linux and other non-Windows servers provide file and print services to clients that support the Microsoft SMB (Server Message Block) and CIFS (Common Internet File System) protocols. Novell Samba is the Linux Samba software that has been modified to work with NetIQ eDirectory. Novell Samba can be used to provide SMB/CIFS access to files on native Linux file systems and Novell Storage Services (NSS) file systems. Users must be eDirectory users who are enabled for Linux User Management (LUM). For information about LUM-enabling your eDirectory users, see the OES 11 SP2: Novell Linux User Management Administration Guide.

IMPORTANT:Novell Samba cannot be used on OES servers where Novell CIFS is installed. Novell CIFS supports only NSS file systems.

Novell Samba must be installed and configured on each node in the cluster. The cluster load script starts the service when you online the Samba cluster resource, and the unload script stops the service when you offline it. For information about using the Samba resource template to create a Samba cluster resource that is based on an LVM volume group, see Configuring Samba for LVM Volume Groups and Novell Cluster Services in the OES 11 SP2: Novell Samba Administration Guide.

IMPORTANT:If you enable both NCP and Novell Samba file access for users, we recommend that you enable the Cross-Protocol Lock (CPL) parameter for NCP Server. CPL helps prevent potential data corruption when files are accessed by non-NCP file access protocols and by other applications that directly access the files with POSIX APIs. CPL is enabled by default. For information, see Configuring Cross-Protocol File Locks for NCP Server in the OES 11 SP2: NCP Server for Linux Administration Guide.

8.1.10 Linux File Access Protocols

You can provide native Linux file access to files on an LVM volume group cluster resource for eDirectory users who are enabled for Linux User Management (LUM). The Linux file access protocols must also be LUM enabled on each node of the cluster. For information about LUM-enabling your eDirectory users and native Linux file access protocols, see the OES 11 SP2: Novell Linux User Management Administration Guide.