# Storage class | replicas? **URL:** \ **Category:** SUSE Storage\ **Created:** [December 18, 2018, 1:07pm UTC](https://forums.suse.com/t/storage-class-replicas/12768 "2018-12-18T13:07:02Z")\ **Posts on this page:** 2\ **Page:** 1
**Author:** ![houtenvan](https://avatars.discourse-cdn.com/v4/letter/h/e495f1/32.png) [@houtenvan](https://forums.suse.com/u/houtenvan)\ **Post date:** [December 18, 2018, 1:07pm UTC](https://forums.suse.com/t/storage-class-replicas/12768/1 "2018-12-18T13:07:02Z")
Hello, I am trying to understand the concept of Longhorn storage class replica setting. I am bit confused because about it because when I deploy HA Elasticsearch or HA Kafka I am using already 3 nodes. **ElasticSearch:** master -\> replica 3 with 3 PVC’s (PV) on 3 different nodes data -\> replica 3 with 3 PVC’s (PV) on 3 different nodes **Total 6 PV** on 3 different nodes (2 for each) Kafka: Zookeeper -\> replica 3 with 3 PVC’s (PV) on 3 different nodes Kafka -\> replica 3 with 3 PVC’s (PV) on 3 different nodes **Total 6 PV** on 3 different nodes (2 for each) Mysql cluster … SO, 12 PV on 3 nodes Now comes the confusion… 12 PVC (PV) with storage class replica set to 3 -\> 36 ??? Wow. I think I don’t understand the concept 🙂 I someone willing to explain? ---
**Author:** ![yasker](https://sea2.discourse-cdn.com/flex022/user_avatar/forums.suse.com/yasker/32/137_2.png) [@yasker](https://forums.suse.com/u/yasker)\ **Post date:** [December 18, 2018, 11:46pm UTC](https://forums.suse.com/t/storage-class-replicas/12768/2 "2018-12-18T23:46:32Z")
Hi @houtenvan Longhorn itself is a generic block storage solution with replications. If the applications already have replications enabled, you may not need Longhorn’s replicas. You can set the `NumberOfReplica` to 1 in the Longhorn StorageClass definition in this case.