How to Create Data Replication of a File System

As discussed in How Does Data Replication between Nodes Work, DataKeeper creates a NetRAID Device which works as RAID1 device.

This guide uses the following parameters as examples. Replace these parameters based on the local environment that DataKeeper is being installed on.

1. See one the following topics to prepare a disk for replication.

• How to Prepare Disks for Replication on AWS
• How to Prepare Disks for Replication on Azure
• How to Prepare Disks for Replication on Google Cloud

2. Mount the disk on the primary node (node-a).

Be sure to check the name of the storage device to mount (such as /dev/xvdb1 or /dev/sdc1).

3. On the LifeKeeper User Interface, define a new resource. Select “Operations” dropdown and click “Create Resource Hierarchy”

4. For the server, select “node-a” and for the Application Recovery Kit, select “Data Replication”. Then click “Next”.

5. For the “Hierarchy Type”, select “Replicate New File System. Select the source disk partition to be used, the desired mount point, and the file system type.

6. Enter the following values. Select the default values.

*Note: For items with a checkmark ( ) review the default values and use the value suggested.

Field	Value
DataKeeper Resource Tag	datarep-datakeeper
Switchback Type	intelligent
File System Resource Tag	/datakeeper
Bitmap File	/opt/LifeKeeper/bitmap__datakeeper
Replication Type	Synchronous

7. Review the selected options, and when ready click “Execute”

8. Once resource creation has completed, select “Extend Resource Hierarchy”

9. Enter the following values in the fields. Select the default values. Then click next.

Field	Value
Template Server	node-a
Resource	/datakeeper
Template Priority	1
Target Server	node-b
Target Priority	10

10. Once Pre-Extend checks have completed, click “Next”

11. When prompted with the “Additional Settings” stage of resource extension, select the “Resource: datarep-datakeeper” dropdown, and enter the following values. Then click “Next”.

Field	Value
Switchback Type	Intelligent
Resource	datarep-datakeeper
Replication Path	172.31.82.48/172.31.92.100 (Note, this communication path will be unique to the IPs assigned to your cluster nodes. The value above applies the lab cluster used in this guide only)
Replication Type	Synchronous
DataKeeper Resource Tag	datarep-datakeeper
Target Disk	/dev/xvdb1 (Note, this disk pertains to the lab environment used in this guide. Select the appropriate target disk for your environment)
Bitmap File	/opt/LifeKeeper/bitmap__datakeeper

12. Review the selected options. When ready, click “Execute”

13. Once the ‘Extend Wizard’ successfully completes, select “Close”.

Now the disk is configured to replicate the data. If you are replicating an existing filesystem, you may see the target in a “resyncing” state. A full initial sync of the data is required when replicating existing filesystems, and is automatically being performed. Once the data is synced, the label will change to “Target”.