Network Bandwidth Throttling - Advanced

Table of Contents

SnapProtect software offers throttling of network traffic to control the bandwidth consumed by various operations. Throttling is configurable at two levels:

Setting Up Network Bandwidth Throttling for Client Computer Groups

Use the steps in this section to set up network bandwidth throttling for client computer groups.

  1. In the CommCell Browser, expand Client Computer Groups, then right-click a client_group and click Properties. The Client Group properties dialog box appears.
  1. Click the Network Throttle tab and select Enable Network Throttling.
  1. Expand Client Computer Groups and/or Client Computers in the Remote Clients or Client Group area, then select the clients or client groups to set throttling for.

    By default, All clients share allocated bandwidth is selected. When this option is set at the client or group level, all remote clients or client groups (picked when configuring throttling for this client) opening a connection to the client with this setting share the bandwidth.

  2. Actual bandwidth throttling is a client-to-client function. Clients within groups inherit the group's setting, but actual throttling takes place between individual clients, shared when more than two clients are involved in point-to-point communication.

    Important: If you clear this option, every selected client and group will throttle at the rate you set, rather than sharing that rate.

  3. Click Add to set a schedule and throttling rate.
    1. In Days of week, select one or more days for the throttling rate to be in effect.
    2. In Time Interval, select Whole Day, or clear that option and enter a Start Time and an End Time for the throttling rate to be in effect.
        Under Throttling Rate, select one of these:
    3. Use Absolute Throttling

      Select Throttle Send and/or Throttle Receive, then enter appropriate values for each that you selected. Sending and receiving will be limited to those speeds, regardless of available bandwidth.

    4. Throttle Relative to bandwidth

      This feature lets you enter a threshold and throttling percentage. While sending or receiving, the client monitors the rate at which it can send and/or receive data. As long as the threshold you enter is below the actual rate, the client sends or receives as fast as the network will allow. If the actual transmission rate falls below the threshold you set, however, the client backs off, sending or receiving data at only the throttling percentage you have set. For example, if your threshold is 500Kb/sec, and your percentage is 40%, transmission is throttled back to 200Kb/sec.

      The client imposes this constraint for a fixed period, then attempts to operate at full speed. If the client finds that conditions have improved (that is, that it can send or receive data at a rate greater than the threshold you set), it stops throttling. If the client cannot send or receive data at a higher threshold rate, it continues to operate at the throttled percentage for another period, then checks again, and so on until the job completes.

      • To enter a sending rate threshold, select If send bandwidth is less than (Kbps) and enter a percentage rate to throttle the sending rate to if that threshold is crossed.
      • To enter a receiving rate threshold, select If receive bandwidth is less than (Kbps) and a percentage rate to throttle the receiving rate to if that threshold is crossed.
  4. Click OK to save the new throttling rule.
  5. The rule you just added appears in the Throttling Schedule area. Click OK again to set the rule for the clients and/or client groups you selected.
  6. From the CommCell Browser, expand Client Computer Groups, then right-click the client_group, mouse over All Tasks and click Push Firewall Configuration.
  7. Click Continue to complete the operation.

Setting Up Network Bandwidth Throttling for Client Computers

Use the steps in this section to set up the network bandwidth throttling for client computers.

  1. In the CommCell Browser,  expand Client Computers, then right-click the client and click Properties.
  2. Click Advanced. The Advanced Client Properties dialog box opens.
  3. Click the Network Throttle tab and select Enable Network Throttling.
  4. By default All clients share allocated bandwidth is selected. When this option is set at the client or group level, all remote clients or client groups (picked when configuring throttling for this client) opening a connection to the client with this setting share the bandwidth. Actual bandwidth throttling is a client-to-client function. Clients within groups inherit the group's setting, but actual throttling takes place between individual clients, shared when more than two clients are involved in point-to-point communication.

    Important: If you clear this option, every selected client and group will throttle at the rate you set, rather than sharing that rate.

  5. Click Add to set a schedule and throttling rate.
    • In Days of week, select one or more days for the throttling rate to be in effect.
    • In Time Interval, select Whole Day, or deselect that option and enter a Start Time and an End Time for the throttling rate to be in effect.
        Under Throttling Rate, select one of these:
    • Use Absolute Throttling

      Select Throttle Send and/or Throttle Receive, then enter appropriate values for each that you selected. Sending and receiving will be limited to those speeds, regardless of available bandwidth.

    • Throttle Relative to bandwidth

      This feature lets you enter a threshold and throttling percentage. While sending or receiving, the client monitors the rate at which it can send and/or receive data. As long as the threshold you enter is below the actual rate, the client sends or receives as fast as the network will allow. If the actual transmission rate falls below the threshold you set, however, the client backs off, sending or receiving data at only the throttling percentage you have set. For example, if your threshold is 500Kb/sec, and your percentage is 40%, transmission is throttled back to 200Kb/sec.

      The client imposes this constraint for a fixed period, then attempts to operate at full speed again. If it finds that conditions have improved (that is, that it can now send or receive data at a rate greater than the threshold you set), it stops throttling. If it still cannot send send or receive above the threshold rate, it continues to operate at the throttled percentage for another period, then checks again, and so on until the job completes.

      • Select If send bandwidth is less than (Kbps) to enter a sending rate threshold, and a percentage rate to throttle the sending rate to if that threshold is crossed.
      • Select If receive bandwidth is less than (Kbps) to enter a receiving rate threshold, and a percentage rate to throttle the receiving rate to if that threshold is crossed.
  6. Click OK to save the new throttling rule.
  7. The rule you just added appears in the Throttling Schedule area. Click OK again to set the rule for the clients and/or client groups you selected.
  8. From the CommCell Browser, expand Client Computers, then right-click the client, mouse over All Tasks and click Push Firewall Configuration.
  9. Click Continue to complete the operation.

Setting Up Network Bandwidth Throttling for MediaAgents

Use the steps in this section to set up network bandwidth throttling for MediaAgents.

  1. In the CommCell Browser, expand  Storage Resources > MediaAgents.
  2. Right-click the mediaAgent_name and click Properties. The MediaAgent Properties dialog box opens.
  3. Click the Network Throttle tab and select Enable Network Throttling.
  1. Expand Client Computer Groups and/or Client Computers in the Remote Clients or Client Group area, then select the clients or client groups to set throttling for.

    By default, All clients share allocated bandwidth is selected. When this option is set at the client or group level, all remote clients or client groups (picked when configuring throttling for this client) opening a connection to the client with this setting share the bandwidth.

  2. Actual bandwidth throttling is a client-to-client function. Clients within groups inherit the group's setting, but actual throttling takes place between individual clients, shared when more than two clients are involved in point-to-point communication.

    Important: If you clear this option, every selected client and group will throttle at the rate you set, rather than sharing that rate.

  1. Click Add to set a schedule and throttling rate.
    • In Days of week, select one or more days for the throttling rate to be in effect.
    • In Time Interval, select Whole Day, or clear that option and enter a Start Time and an End Time for the throttling rate to be in effect.
        Under Throttling Rate, select one of these:
    • Use Absolute Throttling

      Select Throttle Send and/or Throttle Receive, then enter appropriate values for each that you selected. Sending and receiving will be limited to those speeds, regardless of available bandwidth.

    • Throttle Relative to bandwidth

      This feature lets you enter a threshold and throttling percentage. While sending or receiving, the client monitors the rate at which it can send and/or receive data. As long as the threshold you enter is below the actual rate, the client sends or receives as fast as the network will allow. If the actual transmission rate falls below the threshold you set, however, the client backs off, sending or receiving data at only the throttling percentage you have set. For example, if your threshold is 500Kb/sec, and your percentage is 40%, transmission is throttled back to 200Kb/sec.

      The client imposes this constraint for a fixed period, then attempts to operate at full speed again. If it finds that conditions have improved (that is, that it can now send or receive data at a rate greater than the threshold you set), it stops throttling. If it still cannot send send or receive above the threshold rate, it continues to operate at the throttled percentage for another period, then checks again, and so on until the job completes.

      • Select If send bandwidth is less than (Kbps) to enter a sending rate threshold, and a percentage rate to throttle the sending rate to if that threshold is crossed.
      • Select If receive bandwidth is less than (Kbps) to enter a receiving rate threshold, and a percentage rate to throttle the receiving rate to if that threshold is crossed.
  2. Click OK to save the new throttling rule.
  3. The rule you just added appears in the Throttling Schedule area. Click OK again to set the rule for the clients and/or client groups you selected.
  4. Right-click the mediaAgent_name, then mouse over All Tasks and click  Push Firewall Configuration.
  5. Click Continue to complete the operation.

Disabling Network Bandwidth Throttling

To disable network bandwidth throttling for client computer groups, client computers and MediaAgents, follow these steps:

  1. In the CommCell Browser:
    1. If the computer is a Client Computer or Client Computer Group, right-click the client_name or client_group_name, then click Properties. In the Properties dialog, click Advanced.
    2. If the computer is a MediaAgent, expand Storage Resources > MediaAgents, then right-click the mediaAgent_name and click Properties.
  2. In the Properties dialog box, click the Network Throttle tab.
  3. In Remote Clients or Client Group, clear all selected computers and groups.
  4. In Throttling Schedule, delete all defined schedules.
  5. Clear the Enable Network Throttling option.
    1. If the computer is a Client or Client Group, click OK to close the Advanced Client Properties dialog box. Click OK again to close the Client Properties dialog box.
    2. If the computer is a MediaAgent, click OK to close the MediaAgent Properties dialog box.

Setting Up Network Bandwidth Throttling for Subclients

Network bandwidth throttling for a subclient is set on a per-Network-Agent basis.

Setting Network Bandwidth and Network Agents for a Backup Operation

For most iDataAgents, network bandwidth can be established from the subclient properties. For some database agents, this option is available at the Instance level.

All subclients except those using NAS iDataAgents support network bandwidth throttling.

To set a limit for network bandwidth and the number of concurrent network agents for a subclient backup operation, perform these steps:

  1. In the CommCell Browser, expand Client Computers > client_name > agent.
  2. Click a backup_set_name, then on the backup_set tab, right-click a subclient and click Properties.
    • If your iDataAgent is DB2, DB2 MultiNode, Informix, Oracle, Oracle RAC, SAP, or Sybase, right-click an instance, then click Properties.
  3. Click the Storage Device tab, then the Data Transfer Option tab.
    • Set the maximum number of Network Agents to run concurrently when performing a subclient or instance backup.
    • Select the Throttle Network Bandwidth (MB/HR) option, then enter the throughput limit as needed. Note that the SnapProtect software throttles the transfer on a per-network-agent basis.
  4. Click OK to save your changes.

Setting Network Bandwidth and Network Agents for Multiple Subclients Using Subclient Policy

For iDataAgents that support subclient policy, bandwidth throttling can be set while creating multiple subclients, by using a subclient policy.

Use these steps to set the Network Bandwidth and Network Agents while creating multiple subclients:

  1. From the CommCell Browser, expand Policies > Subclient Policies.
  2. Right-click Subclient Policies, then click New Subclient Policy. The New Subclient Policy dialog box opens.
  3. Click in the Name box, then enter a name for your subclient policy.
  4. Click the iDataAgent box and select Windows File System.
  5. Click once in the Storage Policy column cell and select a storage policy for the default subclient.
  6. Click the Association tab and select the backup set on the client that you want to associate with this subclient policy.
  7. Click the General tab, then select the default subclient row and click Edit.
  8. Click the Content tab and enter the contents for the subclient by browsing to them or by entering their path.
  9. Click the Storage Device tab and select the storage policy.
  10. Click the Data Transfer Option tab.
    1. Enter the number of Network Agents that must be used to perform backup operations on the subclient/instance.
    2. Click the Throttle Network Bandwidth (MB/HR) option, then enter a throughput value. Note that throttling is done on a per-Network-Agent basis.
  11. Click OK to save the changes.
  12. Click OK to complete this operation.

The default subclient is automatically created in all the clients with which the subclient policy is associated.

Setting Network Bandwidth Throttling at the Storage Policy Level for Auxiliary Copy

Setting throttling at the storage policy level is an alternative to the more generic approach of setting throttling between any two computers (see the Tip below), but it only applies to auxiliary copy jobs, and cannot be scheduled.

You can limit bandwidth between two computers (any combination of clients or MediaAgents), for all network traffic regardless of the operation being performed. See:

That approach has the additional advantage of letting you set a schedule (time of day, days of week) for the throttling to be in effect.

The storage policy bandwidth setting option lets you limit the network throughput consumed by an auxiliary copy operation. The default limit is 500 megabytes per hour, per stream.

Configure the network for transferring the data in auxiliary copy operation with these steps:

  1. From the CommCell Browser, expand Policies > Storage Policies.
  2. Right-click the storage_policy_copy, then click Properties.
  3. Important: The storage policy copy here cannot be the one named Primary. It must be a copy created with a different name.

  4. Click the Advanced tab and then select Throttle Network Bandwidth per Stream (MB/HR) check box.
  5. In Throttle Network Bandwidth per Stream (MB/HR) box, enter or select the bandwidth limit.
  6. Click OK.

    Once you configure Throttle Network Bandwidth per Stream and assign specific value, during an Auxiliary Copy operation, the Auxiliary Copy Job Details for Job ID dialog box indicates:

    • The size in the Current Throughput (GB/Hr), set on the Streams tab may display higher than the amount of size specified in the Throttle Network Bandwidth per Stream. This is because the size displayed in the Current Throughput (GB/Hr) column is in application data size. However, note that the Current Throughput honors the value set in the Throttle Network Bandwidth per Stream even though the data size value exceeds during the Auxiliary Copy operation.