NetBackup™ Backup Planning and Performance Tuning Guide

Last Published:
Product(s): NetBackup & Alta Data Protection (10.4, 10.3.0.1, 10.3, 10.2.0.1, 10.2, 10.1.1, 10.1, 10.0.0.1, 10.0, 9.1.0.1, 9.1, 9.0.0.1, 9.0, 8.3.0.2, 8.3.0.1, 8.3)
  1. NetBackup capacity planning
    1.  
      Purpose of this guide
    2.  
      Changes in Veritas terminology
    3.  
      Disclaimer
    4.  
      How to analyze your backup requirements
    5.  
      How to calculate the size of your NetBackup image database
    6. Sizing for capacity with MSDP
      1. Key sizing parameters
        1.  
          Data types and deduplication
        2.  
          Determining FETB for workloads
        3.  
          Retention periods
        4.  
          Change rate
        5.  
          Replication and duplication of backups
        6.  
          Sizing calculations for MSDP clients
    7.  
      About how to design your OpsCenter server
  2. Primary server configuration guidelines
    1.  
      Size guidance for the NetBackup primary server and domain
    2.  
      Factors that limit job scheduling
    3.  
      More than one backup job per second
    4.  
      Stagger the submission of jobs for better load distribution
    5.  
      NetBackup job delays
    6.  
      Selection of storage units: performance considerations
    7.  
      About file system capacity and NetBackup performance
    8.  
      About the primary server NetBackup catalog
    9.  
      Guidelines for managing the primary server NetBackup catalog
    10.  
      Adjusting the batch size for sending metadata to the NetBackup catalog
    11.  
      Methods for managing the catalog size
    12.  
      Performance guidelines for NetBackup policies
    13.  
      Legacy error log fields
  3. Media server configuration guidelines
    1. NetBackup hardware design and tuning considerations
      1.  
        PCI architecture
      2.  
        Central processing unit (CPU) trends
      3.  
        Storage trends
      4.  
        Conclusions
    2. About NetBackup Media Server Deduplication (MSDP)
      1.  
        Data segmentation
      2.  
        Fingerprint lookup for deduplication
      3.  
        Predictive and sampling cache scheme
      4.  
        Data store
      5.  
        Space reclamation
      6.  
        System resource usage and tuning considerations
      7.  
        Memory considerations
      8.  
        I/O considerations
      9.  
        Network considerations
      10.  
        CPU considerations
      11.  
        OS tuning considerations
      12. MSDP tuning considerations
        1.  
          Sample steps to change MSDP contentrouter.cfg
      13. MSDP sizing considerations
        1.  
          Data gathering
        2.  
          Leveraging requirements and best practices
    3.  
      Cloud tier sizing and performance
    4. Accelerator performance considerations
      1.  
        Accelerator for file-based backups
      2.  
        Controlling disk space for Accelerator track logs
      3.  
        Accelerator for virtual machine backups
      4.  
        Forced rescan schedules
      5.  
        Reporting the amount of Accelerator data transferred over the network
      6.  
        Accelerator backups and the NetBackup catalog
  4. Media configuration guidelines
    1.  
      About dedicated versus shared backup environments
    2.  
      Suggestions for NetBackup media pools
    3.  
      Disk versus tape: performance considerations
    4.  
      NetBackup media not available
    5.  
      About the threshold for media errors
    6.  
      Adjusting the media_error_threshold
    7.  
      About tape I/O error handling
    8.  
      About NetBackup media manager tape drive selection
  5. How to identify performance bottlenecks
    1.  
      Introduction
    2.  
      Proper mind set for performance issue RCA
    3.  
      The 6 steps of performance issue RCA and resolution
    4. Flowchart of performance data analysis
      1.  
        How to create a workload profile
  6. Best practices
    1.  
      Best practices: NetBackup SAN Client
    2. Best practices: NetBackup AdvancedDisk
      1.  
        AdvancedDisk performance considerations
      2.  
        Exclusive use of disk volumes with AdvancedDisk
      3.  
        Disk volumes with different characteristics
      4.  
        Disk pools and volume managers with AdvancedDisk
      5.  
        Network file system considerations
      6.  
        State changes in AdvancedDisk
    3.  
      Best practices: Disk pool configuration - setting concurrent jobs and maximum I/O streams
    4.  
      Best practices: About disk staging and NetBackup performance
    5.  
      Best practices: Supported tape drive technologies for NetBackup
    6. Best practices: NetBackup tape drive cleaning
      1.  
        How NetBackup TapeAlert works
      2.  
        Disabling TapeAlert
    7.  
      Best practices: NetBackup data recovery methods
    8.  
      Best practices: Suggestions for disaster recovery planning
    9.  
      Best practices: NetBackup naming conventions
    10.  
      Best practices: NetBackup duplication
    11.  
      Best practices: NetBackup deduplication
    12. Best practices: Universal shares
      1.  
        Benefits of universal shares
      2.  
        Configuring universal shares
      3.  
        Tuning universal shares
    13. NetBackup for VMware sizing and best practices
      1.  
        Configuring and controlling NetBackup for VMware
      2.  
        Discovery
      3.  
        Backup and restore operations
    14. Best practices: Storage lifecycle policies (SLPs)
      1.  
        Data flow and SLP design best practices
      2.  
        Targeted SLP
      3.  
        Limiting the number of SLP secondary operations to maximize performance
      4.  
        Storage Server IO
    15.  
      Best practices: NetBackup NAS-Data-Protection (D-NAS)
    16.  
      Best practices: NetBackup for Nutanix AHV
    17.  
      Best practices: NetBackup Sybase database
    18.  
      Best practices: Avoiding media server resource bottlenecks with Oracle VLDB backups
    19.  
      Best practices: Avoiding media server resource bottlenecks with MSDPLB+ prefix policy
    20.  
      Best practices: Cloud deployment considerations
  7. Measuring Performance
    1.  
      Measuring NetBackup performance: overview
    2.  
      How to control system variables for consistent testing conditions
    3.  
      Running a performance test without interference from other jobs
    4.  
      About evaluating NetBackup performance
    5.  
      Evaluating NetBackup performance through the Activity Monitor
    6.  
      Evaluating NetBackup performance through the All Log Entries report
    7. Table of NetBackup All Log Entries report
      1.  
        Additional information on the NetBackup All Log Entries report
    8. Evaluating system components
      1.  
        About measuring performance independent of tape or disk output
      2.  
        Measuring performance with bpbkar
      3.  
        Bypassing disk performance with the SKIP_DISK_WRITES touch file
      4.  
        Measuring performance with the GEN_DATA directive (Linux/UNIX)
      5.  
        Monitoring Linux/UNIX CPU load
      6.  
        Monitoring Linux/UNIX memory use
      7.  
        Monitoring Linux/UNIX disk load
      8.  
        Monitoring Linux/UNIX network traffic
      9.  
        Monitoring Linux/Unix system resource usage with dstat
      10.  
        About the Windows Performance Monitor
      11.  
        Monitoring Windows CPU load
      12.  
        Monitoring Windows memory use
      13.  
        Monitoring Windows disk load
    9.  
      Increasing disk performance
  8. Tuning the NetBackup data transfer path
    1.  
      About the NetBackup data transfer path
    2.  
      About tuning the data transfer path
    3.  
      Tuning suggestions for the NetBackup data transfer path
    4.  
      NetBackup client performance in the data transfer path
    5. NetBackup network performance in the data transfer path
      1.  
        Network interface settings
      2.  
        Network load
      3. Setting the network buffer size for the NetBackup media server
        1.  
          Network buffer size in relation to other parameters
      4.  
        Setting the NetBackup client communications buffer size
      5.  
        About the NOSHM file
      6.  
        Using socket communications (the NOSHM file)
    6. NetBackup server performance in the data transfer path
      1. About shared memory (number and size of data buffers)
        1.  
          Default number of shared data buffers
        2.  
          Default size of shared data buffers
        3.  
          Amount of shared memory required by NetBackup
        4.  
          How to change the number of shared data buffers
        5.  
          Notes on number data buffers files
        6.  
          How to change the size of shared data buffers
        7.  
          Notes on size data buffer files
        8.  
          Size values for shared data buffers
        9.  
          Note on shared memory and NetBackup for NDMP
        10.  
          Recommended shared memory settings
        11.  
          Recommended number of data buffers for SAN Client and FT media server
        12.  
          Testing changes made to shared memory
      2.  
        About NetBackup wait and delay counters
      3.  
        Changing parent and child delay values for NetBackup
      4. About the communication between NetBackup client and media server
        1.  
          Processes used in NetBackup client-server communication
        2.  
          Roles of processes during backup and restore
        3.  
          Finding wait and delay counter values
        4.  
          Note on log file creation
        5.  
          About tunable parameters reported in the bptm log
        6.  
          Example of using wait and delay counter values
        7.  
          Issues uncovered by wait and delay counter values
      5.  
        Estimating the effect of multiple copies on backup performance
      6. Effect of fragment size on NetBackup restores
        1.  
          How fragment size affects restore of a non-multiplexed image
        2.  
          How fragment size affects restore of a multiplexed image on tape
        3.  
          Fragmentation and checkpoint restart
      7. Other NetBackup restore performance issues
        1.  
          Example of restore from multiplexed database backup (Oracle)
    7.  
      NetBackup storage device performance in the data transfer path
  9. Tuning other NetBackup components
    1.  
      When to use multiplexing and multiple data streams
    2.  
      Effects of multiplexing and multistreaming on backup and restore
    3. How to improve NetBackup resource allocation
      1.  
        Improving the assignment of resources to NetBackup queued jobs
      2.  
        Sharing reservations in NetBackup
      3.  
        Disabling the sharing of NetBackup reservations
      4.  
        Disabling on-demand unloads
    4.  
      Encryption and NetBackup performance
    5.  
      Compression and NetBackup performance
    6.  
      How to enable NetBackup compression
    7.  
      Effect of encryption plus compression on NetBackup performance
    8.  
      Information on NetBackup Java performance improvements
    9.  
      Information on NetBackup Vault
    10.  
      Fast recovery with Bare Metal Restore
    11.  
      How to improve performance when backing up many small files
    12. How to improve FlashBackup performance
      1.  
        Adjusting the read buffer for FlashBackup and FlashBackup-Windows
    13.  
      Veritas NetBackup OpsCenter
  10. Tuning disk I/O performance
    1. About NetBackup performance and the hardware hierarchy
      1.  
        About performance hierarchy level 1
      2.  
        About performance hierarchy level 2
      3.  
        About performance hierarchy level 3
      4.  
        About performance hierarchy level 4
      5.  
        Summary of performance hierarchies
      6.  
        Notes on performance hierarchies
    2.  
      Hardware examples for better NetBackup performance

Setting the network buffer size for the NetBackup media server

A modern, well configured, operating system with properly written TCP drivers is unlikely to need TCP memory tuning by NetBackup. Accordingly, the best NetBackup configuration is to disable tuning by placing a zero (0) into the NET_BUFFER_SZ file on media servers and Linux/UNIX clients. Simply deleting the file is not equivalent because some NetBackup processes have default setsockopt API calls configured to overcome past external problems with various platforms and drivers. See the following paragraphs for more details and other considerations.

NET_BUFFER_SZ is a tunable media server parameter that can be used to adjust the size of the network buffer space. The operating system uses this buffer space for the connection between the bptm child process and the client process. This buffer space caches either received data from the network (a backup) or written data to the network (a restore). The parameter sets the value for NetBackup to use for the network buffer space, but the operating system may not allow the change.

The NetBackup media server can be configured to request that the operating system use a non-default size for the network buffer space. If the NET_BUFFER_SZ touch file exists, bptm requests that the operating system adjust the size. The operating system may or may not allow the change, depending on the operating system revision and the current TCP tuning.

The following examples are from bptm logs on various platforms. These examples show how bptm records the size that was used and any previous size requested by NetBackup.

For example:

Red Hat

setting receive network buffer to 1049600 bytes

Solaris 10

setting receive network buffer to 65536 bytes
receive network buffer is 64240 bytes

Windows

setting receive network buffer to 1049600 bytes
setting receive network buffer to 1049600 bytes

The default value for this parameter is derived from the NetBackup data buffer size using the following formula:

For backup jobs: (<data_buffer_size> * 4) + 1024

For restore jobs: (<data_buffer_size> * 2) + 1024

For tape:

If the default value for the NetBackup data buffer size is 65536 bytes, the formula results in the following: a default NetBackup network buffer size of 263168 bytes for backups and 132096 bytes for restores.

For disk:

If the default value for the NetBackup data buffer size is 262144 bytes, the formula results in the following: a default NetBackup network buffer size of 1049600 bytes for backups and 525312 bytes for restores.

To set the network buffer size

  1. Create the following files:

    Linux/UNIX 

    /usr/openv/netbackup/NET_BUFFER_SZ
/usr/openv/netbackup/NET_BUFFER_SZ_REST

    Windows

    install_path\NetBackup\NET_BUFFER_SZ
install_path\NetBackup\NET_BUFFER_SZ_REST
  2. Note the following about the buffer files:

    These files contain a single integer that specifies the network buffer size in bytes. The value in each file must be within the value range that the operating system allows. Otherwise, the established connection may behave erratically. For example, to use a network buffer size of 64 kilobytes, the file would contain 65536. If the files contain the integer 0 (zero), the default operating system value for the network buffer size is used. More information about the buffer files is available:

    https://www.veritas.com/support/en_US/article.100016112

    If the NET_BUFFER_SZ file exists and the NET_BUFFER_SZ_REST file does not exist, NET_BUFFER_SZ specifies the network buffer size for backup and restores.

    If the NET_BUFFER_SZ_REST file exists, its contents specify the network buffer size for restores.

    If both files exist, the NET_BUFFER_SZ file specifies the network buffer size for backups. The NET_BUFFER_SZ_REST file specifies the network buffer size for restores.

    Because local backup or restore jobs on the media server do not send data over the network, this parameter has no effect on those operations. This parameter is used only by the NetBackup media server processes that read from or write to the network, specifically, the bptm or bpdm processes. No other NetBackup process uses this parameter.