We currently have a DMS cluster, each agent has its own single Cassandra node (local or hosted on a separate external server).
For the migration towards Cassandra+OpenSearch Cluster, could we repurpose these external (single Cassandra node) servers specifically for the C+OS cluster?
In theory it sounds simple, reduce the resources of the current external VMs and with those resources create a new Linux VMs to be used for the C+OS cluster
However I'm not sure if this is a good way, if it's feasible or what kind of issues to expect.
I'm currently thinking of:
- Some downtime is expected to reduce the resources of the current VMs
- We should be vigilant when reducing the resources (compaction > requires extra disk space, page file > memory,...)
- It'll also depend on the physical hardware capacities
To come back on this topic.
We agreed that the safest way forward, was the most easy method. We'll use new HW to migrate to the new DB clusters.
=> That way, we keep it simple and avoid issues due to complexities.
This does mean that we'll have a series of decommissioned servers. These could be repurposed within the company or if needed, some could even be added to the new DB clusters to enforce the capacity.