3.5 Configuring the Target Service Agent for File System

TSAFS provides configurable parameters to help tune its performance. It also provides configurable parameters to control certain specific features that are supported by it.

3.5.1 Using iManager

Complete the following steps to configure the parameters used by TSA:

In iManager, click SMS Backup and Restore, then click TSAFS Options.
Select the server for which you need to modify the TSA configuration settings, using the eDirectory object selector.
Enter the following values and click OK.
- TSA Mode: TSA Mode can be used to expose NSS as a native Linux file system (Linux Mode) or emulate NetWare file system semantics (NetWare Mode) on OES 11 SP3.
  
  If the Dual Mode is selected, both NetWare and Linux semantics are simultaneously exposed and can be used independently of each other. By default, the TSA Mode is set to Linux.
  
  The changed value takes effect when you reload the tsafs module.
- Read Buffer Size: The number of data bytes read from the file system by a single read operation.
  
  This parameter is based on the buffer size requested by the engine. For example, if the engine requests 64 KB of data for each read operation, set the buffer size to 64 KB to allow the TSAFS to service the engine better. By default this is set to 65536 bytes.
  
  The modified value takes effect when you reload the tsafs module.
- Read Threads Per Job: The number of read-ahead threads for a job. This enables the TSAFS to read data ahead of the engine request during backup. This switch is based on the number of processors in the system. The default value is 4 for a single or dual processor system. Set the read threads to a higher value if the system has more processors.
  
  The changed value takes effect when you reload the tsafs module.
- Read Thread Allocation: The percentage of Read Threads Per Job that processes a data set.
  
  Read Thread Allocation can be used to control the maximum number of read threads that may be allocated to process a single data set. By default, the Read Thread Allocation is set to 100 (%). It can have a value in the range 10 (%) to 100 (%). It is recommended that this value be set to 100 (%) if the backup application requests data sets serially.
- Read Ahead Throttle: The maximum number of data sets that the TSA processes simultaneously.
  
  Read Ahead Throttle can be used to limit the number of simultaneous data sets that are being cached. In certain runtime scenarios, it helps in overriding the Read Thread Allocation in order to complete processing of large data sets. By default, the Read Ahead Throttle is set to 2. It can have a value in the range 1 to 32.
- Cache Memory Threshold: The percentage of unallocated server memory that the TSA can utilize to store cached datasets. This represents a maximum percentage value of unallocated server memory that the TSA uses to store cached datasets. The default value is 25% of unallocated server memory. The cache memory utilized by the TSA is dynamically reset based on the available unallocated memory.
  
  The modified value takes effect when you reload the tsafs module.
- Enable Caching: This option can be used to specify if the TSA should do predictive caching during backups. Caching improves backup performance, on certain workloads, by prefetching files in memory. By default, Enable Caching is selected.
  
  The modified value takes effect when you reload the tsafs module.
- Enable Clustering: Determines cluster support. If the backup server does not support clusters, this option is disabled. Select this option if the TSA is running on a cluster node and the backup engine is cluster-enabled. Deselect it if the TSA is running on a non-cluster node or the backup engine is not cluster-enabled. This is selected by default.
  
  Running a cluster-enabled TSA on a non-cluster node does not affect functionality in any way.
  
  The modified value takes effect when you reload the tsafs module.

3.5.2 Using the Command Line

The Storage Management Data Requestor (SMDR) is a daemon process that holds the information regarding Target Service Agents (TSA) that have registered to it.

The process of registering or de-registering a TSA with SMDR is referred to as a loading or unloading the TSA. The TSAs should be registered with SMDR for the backup engines to access the specific target.

The /opt/novell/sms/bin/smsconfig command can be used to load or unload the (TSA) with the SMDR daemon:

smsconfig [ -l | -u | -t] [TSA module name] [TSA options] ...

For example:

smsconfig -r, --refresh	Specify this option in Cluster Unload scripts to inform SMDRD regrading the cluster resource failover. This option must be passed with -p <pool_servername>.This option unregisters the pool and is supported with TSAFS.
smsconfig -l tsafs	Registers the TSA, tsafs with SMDR
smsconfig -u tsafs	De-registers the TSA, tsafs from SMDR
smsconfig -t	List the TSAs currently registered with SMDR
smsconfig -l tsafs --tsaMode=Linux	Set the tsamode to linux to expose NSS as a native Linux file system. This is the default. Set the tsamode to netware to expose NSS with NetWare file system semantics. Set the tsamode to dual, if both NetWare and Linux semantics should be simultaneously exposed and be used independently of each other.

The TSAs also expose their command line configuration interface to the user through smsconfig, which enables the user to configure the TSAs. For example, the following command can be used to see TSAFS configurable parameters:

smsconfig -l tsafs --help

TSAFS can be configured during registration as shown in the following example:

smsconfig -l tsafs --ReadThreadsPerJob=6

This configuration persists till the TSA is unloaded.

smsconfig -r tsafs -p ClusterPool_Server

On a cluster resource failover, the specified pool is unregistered.

For more information regarding smsconfig and tsafs configurable parameters, see the smsconfig(1) and tsafs(1) man pages.

For advanced configuration, see Section 5.3, Fine-Tuning SMS Performance.

To enable additional backup features, see Section 4.1.4, Additional Backup Features.

3.5.3 Using a Configuration File

The TSAFS configuration file is located at /etc/opt/novell/sms/tsafs.conf on OES servers. When the TSA is loaded, it reads the configuration file for its default configuration.

For information, see the tsafs.conf(5) man page.