Spectrum Protect Server Options | Teradata DSA | DSE - 17.06 - Spectrum Protect Server Options - Data Stream Extensions

Teradata® DSA - DSE for IBM Spectrum Protect Installation, Configuration, and Upgrade Guide

Data Stream Architecture
Data Stream Extensions
January 2021

If needed for your site, adjust the Spectrum Protect server option values for the Spectrum Protect server (dsmserv.opt) and the Spectrum Protect Storage Agent (dsmsta.opt). Use SETOPT on the Spectrum Protect server to set these global variables.

Spectrum Protect Server Option Description
COMMTIMEOUT Specifies how long the server waits for an expected client message during an operation that causes a Spectrum Protect database update. If a message does not arrive before the specified wait period, the server ends the session with the client.

To prevent clients from timing out while backing up large files or during a heavy network load, increase the time-out value.

MAXNUMMP Setting in the DEFINE NODE and UPDATE NODE commands, determines the maximum number of mount points possible for this node.

A mount point is a tape or a file device class volume. Parallel (concurrent) backup and restore operations that work with sequential file or tape storage pools require multiple mount points. The resource utilization client option governs the maximum number of concurrent backup or restore sessions that the client can use. The MAXNUMMP server parameter, on the UPDATE NODE or REGISTER NODE commands, and the MOUNTLIMIT setting in the DEFINE DEVCLASS and UPDATE DEVCLASS commands, determines how many mount points a client node can use, at one time.

Configure these settings according to your requirements and available hardware. Take into account the number of mount points that all nodes might need, at any one time.

For example, if you have four client nodes and only eight tape drives, if you configure all four nodes with MAXNUMMP 8, one node can seize all of the tape drives, leaving no tape drives for other nodes to use.

MOUNTLIMIT Setting in the DEFINE DEVCLASS and UPDATE DEVCLASS commands, determines how many mount points a client can use at once.
  • Default: Set to DRIVES instead of a number. DRIVES specifies that when a mount point is allocated, the number of drives defined and online in the library is used to calculate the true value.
  • EXTERNAL library types: Do not specify DRIVES. Specify the number of drives for the library as the MOUNTLIMIT value.
IDLETIMEOUT Specifies the amount of time, in minutes, that a client session can be idle before the server cancels the session.

To prevent clients from timing out due to a heavy network load in the environment, increase the time-out value in the dsmsta.opt file for the storage server and SETOPT on the Spectrum server.

If the time-out value is increased, a large number of idle sessions could prevent other users from connecting to the server.
RESOURCETIMEOUT Specifies the maximum number of minutes that a storage agent waits for a resource on the server. Range is 1 to 60 minutes. SETOPT on the Spectrum server. Default: 60
TXNGROUPMAX Indicates the maximum number of logical files (client files) that a client can send to the server in a single transaction. The server might create multiple aggregates for a single transaction, depending on the size of the transaction.

The TXNGROUPMAX option controls the number of files allowed in a transaction. Although the maximum value allowed is 65000, Spectrum Protect limits the number of objects restored at the same time to 4080 objects. Set this option to 4080.

Teradata Extension for Spectrum Protect maps DSE backup files to a series of smaller storage objects or files segments with an object size of 2 GB. Therefore, the maximum size of a single backup cannot exceed 4080 * 2 GB, or approximately 8.1 TB.