The basic

bsr replicates host volumes within a fail-over cluster in real time over the network to make them redundant.

Synchronization and Replication

To replicate, volume data on both hosts must first match. To achieve this, the process of copying data in disk block units Data is copied from the source to the target via in disk block units over the network. This process is called synchronization. Only when synchronization is complete does it move to the replication state.

Replication is an operation that reflects the change in real time to the target side when data on the source side is changed by write I/O. Synchronization operates slowly in the background, while replication occurs quickly in the context of local I/O.

Although synchronization and replication operate separately, they can occur simultaneously at one point. In other words, since replication can be processed simultaneously while synchronization is being performed (if the actual operating node is synchronizing, you should think that these two operations are always processed simultaneously by write I/O during operation), the processing bandwidth between them is reduced. It is important to properly adjust within the range of maximum network processing bandwidth. For information on setting the sync band, see Adjust sync speed.

Replication works in the following way:

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The application writes data to the block device while replicating it in real time.

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Real-time replication does not affect other application services or system elements.

Replicate synchronously or asynchronously

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In the synchronous method, replication is considered complete when the replication data has been written to the local disk and the target host's disk.

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Replication works in the following way:

• The application writes data to the block device while replicating it in real time.

• Real-time replication does not affect other application services or system elements.

• Replicate synchronously or asynchronously

  • In the synchronous method, replication is considered complete when the replication data has been written to the local disk and the target host's disk.

  • The asynchronous method treats replication as complete when replication data is written to the local disk and transmitted to the target host.

Synchronization and replication operate separately within bsr, but can occur simultaneously at a single point in time. In other words, since replication can be processed simultaneously while synchronization is being performed (the operating node processes synchronization and simultaneously replicates write I/O that occurs during operation), the throughput between each node must be appropriately adjusted within the range of the maximum network bandwidth. . For information on setting the sync band, see https://mantech.jira.com/wiki/spaces/BUGE/pages/1419935915/Working#Adjusting-the-synchronization-speed.

Kernel drivers

The core engine of BSR is implemented as a kernel driver.

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