Clusterdisksonly

The clusterdisksonly option specifies whether the Tivoli® Storage Manager backup-archive client allows the backup of only clustered disks in specific environments.

Tivoli Storage Manager allows the backup of only clustered disks when the client is running in the following environments:

In a Microsoft Cluster Server (MSCS)
When failover clustering is employed on a supported Windows Server client
In a VERITAS Cluster Server (VCS) environment, when you set clusternode yes

The Tivoli Storage Manager backup-archive client previously only allowed backups and restores of data on clustered drives that were mounted as a drive letter.

It is common to find clustered drives that are mounted as volume mount points. Windows Server operating systems allow users to surpass the 26-drive-letter limitation by allowing volume mount points to be defined on a clustered server. Tivoli Storage Manager can protect data on cluster disks that are mounted as drive letters on Windows Server OS computers. Tivoli Storage Manager can also protect data on cluster disks that are mounted as volume mount points. The backup-archive client can automatically determine whether a volume that is using a volume mount point is a cluster volume.

When you set clusterdisksonly yes, the backup-archive client continues to segregate local drives from cluster drives when it evaluates the ALL-LOCAL domain option. When clusterdisksonly no is specified, you must explicitly define the backup domains. When clusterdisksonly no is specified, the backup-archive client also bypasses enumeration of cluster resources to determine which resources represent cluster drives.

Supported Clients

This option is valid for all supported Windows Server clients.

Options File

Place this option in the client options file (dsm.opt).

Syntax


                     .-Yes-.   
>>-CLUSTERDISKSOnly--+-----+-----------------------------------><
                     '-No--'

Parameters

Yes: Specifies that the Tivoli Storage Manager allows only the processing of cluster drives. Yes is the default.
No: Specifies that the Tivoli Storage Manager allows the processing of any disk when clusternode yes is set.

Examples

Scenario 1: Back up a node that manages the local (non-clustered) drives and the system state information

This is the node that is dedicated to the restoration of the physical system if a hardware failure occurs. There are no clustered drives that are mounted as volume mount points.

Options file:

CLUSTERNODE NO (default)    
CLUSTERDISKSONLY YES (default)    
DOMAIN ALL-LOCAL (default)    
EXCLUDE c:\...\file.txt

Scenario 1b: Back up a node that manages the local (non-clustered) drives and the system state information and bypass enumeration of cluster resources

This is a scenario similar to scenario 1, which can be deployed if the Tivoli Storage Manager backup-archive client takes an inappropriate amount of time during startup processing. During initialization of the backup-archive client, all of the cluster resources are enumerated to determine which resources represent cluster disk devices. This processing can be skipped by setting clusterdisksonly no.

Options file:

CLUSTERNODE NO (default)
CLUSTERDISKSONLY NO
DOMAIN C: D: (local drives must be explicitly enumerated)
EXCLUDE c:\...\file.txt

Scenario 2: Back up a node that manages the clustered drives within a cluster resource group and bypass enumeration of cluster resources

This is a scenario that can be deployed if the Tivoli Storage Manager backup-archive client takes an inappropriate amount of time during startup processing. During initialization of the backup-archive client, all of the cluster resources are enumerated to determine which resources represent cluster disk devices. This processing can be skipped by setting clusterdisksonly no.

Options file:

CLUSTERNODE YES 
CLUSTERDISKSONLY NO
DOMAIN f: g:
EXCLUDE f:\...\file.txt

Scenario 3: Back up a node that manages the clustered drives within a cluster resource group, by using volume mount points as cluster resources

In this scenario, it is assumed that the node is responsible for backing up a cluster resource group that has two drives, f: and f:\mnt. There are clustered drives that are mounted as volume mount points (Windows Server operating systems). Ensure that you define the incremental processing domain as only the volumes within a cluster resource group. If you have multiple cluster resource groups, assign a unique Tivoli Storage Manager node to manage each cluster resource group.

Options file

CLUSTERNODE YES
CLUSTERDISKSONLY YES
DOMAIN f: f:\mnt
EXCLUDE f:\mnt\...\file.txt

Table 1 lists the clusternode and clusterdisksonly combinations.

Table 1. Clusternode and clusterdisksonly combinations
Clusternode	Clusterdisksonly	When to use
no	yes	This is the default behavior if nothing is specified; since the clusterdisksonly option is set to clusterdisksonly yes, the cluster disk map is built. This combination is used for backing up local drives.
yes	yes	This is the default way to run in a cluster node to back up cluster disks, including disks that are exposed as mount points; the cluster disk map is built.
yes	no	For clients that run on Windows Server operating systems, you must specify clusterdisksonly no only if you want to bypass cluster volume enumeration for performance reasons.