Often it is required to migrate the data from one storage backend to another backend. The most common use case of data migration is from the Consul backend to the integrated storage backend.
For achieving this we can definitely use this learn guide. Although, this is applicable only for Enterprise Customers. Using the former approach has the following disadvantages:
- Larger downtime windows may be required to perform the migration.
- Sometimes issues may be encountered while migrating the data like network fluctuations, nodes get overwhelmed due to high load resulting in inconsistent/failed migrations. All these factors may lead to the cluster in sealed state.
- If the old consul cluster is decommissioned, then the cluster may have issues in returning to the working state.
To avoid the above mentioned challenges the following approach can be followed:
- Using the integrate storage backend, create a brand new cluster with the desired configuration.
- Set up a DR replication between the 2 clusters i.e between the cluster with consul backend & the cluster with the integrated storage backend using this documentation.
- Once the DR replication is setup between the 2 clusters then, the new cluster with the integrated storage can be promoted & the old consul cluster can be demoted.
- Later the old consul cluster can decommissioned.
The above approach has following advantages:
- Reduced downtime for the migration. As the cluster will encounter the downtime only for the period when the cutover is being performed.