Single rs possible?

MongoDB Percona Operator for MongoDB
1

Description:

Is installing a single rs possible? Not 3 replicas, 1.

I don’t want to waste the limited resources of the cluster. I have rdb underlying with 3 replicas, so I don’t need another layer of 3 nodes consuming at least 2 vcpu and 2GB RAM.

I could imagine 2 instances and 1 arbiter, or simply have just 1 instance, configured as a rs, because changelogs require it to be a rs.

Steps to Reproduce:

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Version:

8.0.12

Logs:

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Expected Result:

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Actual Result:

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Additional Information:

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2

Yes, it is possible. Some people use this method to feed their debezzium since debezzium feeds from the oplog, and the oplog is only available with a replication setup.,
You can just follow the below and skip the other nodes:

3

UnsafeFlags section in cr.yaml may help you to avoid any manual manipulation: Custom Resource options - Percona Operator for MongoDB