Configuring number of replicas when there are more than 2 server groups (3 groups/zones)

Couchbase Server
1

I am new to Couchbase. We are planning to use 3 server groups one for each zone in our GKE cloud. From the documentation, (https://docs.couchbase.com/server/6.0/learn/clusters-and-availability/groups.html#group-failover-and-service-availability), it’s clear the case of 2 groups (each bucket has a replica in the other group). What happens in case of 3 groups? will each bucket has 2 replicas (in the other two groups).

I am assuming there should be a way to configure number of replicas to maintain the cluster. Can you please let me know where to configure that if that is the case/or point me to any documentation?

Please do let me know if you have any questions.

Regards.

2

Nvm, kubectl describe on the “couchbasecluster” object gav me details.

i.e; even though there are more than 2 groups - in my case 3, there is only one replica.

not sure where to configure number of replicas though?

Buckets:
Compression Mode: passive
Conflict Resolution: seqno
Enable Flush: true
Eviction Policy: valueOnly
Io Priority: high
Memory Quota: 200
Name: mycache_cache
Replicas: 1
Type: couchbase
Compression Mode: passive
Conflict Resolution: seqno
Enable Flush: true
Eviction Policy: valueOnly
Io Priority: high
Memory Quota: 200
Name: mycache
Replicas: 1
Type: couchbase
Compression Mode: passive
Conflict Resolution: seqno
Enable Flush: true
Eviction Policy: valueOnly
Io Priority: high
Memory Quota: 200
Name: mycache_site
Replicas: 1
Type: couchbase
Compression Mode: passive
Conflict Resolution: seqno
Enable Flush: true
Eviction Policy: valueOnly
Io Priority: high
Memory Quota: 200
Name: mycache_token
Replicas: 1
Type: couchbase
Compression Mode: passive
Conflict Resolution: seqno
Enable Flush: true
Eviction Policy: valueOnly
Io Priority: high
Memory Quota: 200
Name: mycache_user
Replicas: 1
Type: couchbase

3

Hi @NN_P,

If you’re referring to replicas within a cluster, these are configured at the bucket level. If you’re using the Kubernetes operator, you can just pick a number for replicas (maximum of 3). An example here: https://docs.couchbase.com/operator/2.0/reference-couchbasebucket.html

If you’re not using the operator, you can set the replicas via the UI, API, CLI, etc. Here’s an example in the docs of using the UI to set the number of replicas: https://docs.couchbase.com/server/current/manage/manage-buckets/create-bucket.html