How bandwidth limiting works
When a backup starts, NetBackup reads the bandwidth limit configuration then determines the appropriate bandwidth value and passes it to the client. NetBackup computes the bandwidth limit that is based on the current set of active backups on the subnet and the new backup that starts. Backups that start later are not considered. NetBackup does not include local backups in its calculations.
The NetBackup client software enforces the bandwidth limit. Before a buffer is written to the network, client software calculates the current value for kilobytes per second and adjusts its transfer rate if necessary.
As the number of active backups increase or decrease on a subnet, NetBackup dynamically adjusts the bandwidth limits on that subnet. If additional backups
378 Host properties
Master server, media server, and client host properties
are started, the NetBackup server instructs the other NetBackup clients that run on that subnet to decrease their bandwidth setting. Similarly, bandwidth per client is increased if the number of clients decreases. Changes to the bandwidth value occur on a periodic basis rather than as backups stop and start. The periodic changes reduce the number of bandwidth value changes that are required.
Bandwidth throttle setting for the range of IP addresses
This area lists the clients in the range of added IP addresses.
From IP address
The From IP address field specifies the beginning of the IP address range of the clients and networks to which the entry applies. An example is 10.1.1.2
To IP address
The To IP address field specifies the end of the IP address range of the clients and networks to which the entry applies. An example is 10.1.1.9
Bandwidth
The Bandwidth field specifies the bandwidth limitation in kilobytes per second. A value of 0 disables the limits for an individual client or the range of IP addresses covered by the entry.
For example, a value of 200 indicates 200 kilobytes per second.
Bandwidth throttle settings list
The bandwidth throttle settings list indicates the clients in the range of IP addresses that were added.
Add button
Click the Add button to prepare an entry using the From, To, and Bandwidth fields and add it to the bandwidth table. An entry is added for each of the selected clients.
