Is it possible to have a Cassandra Cluster, without Elastic?
Checking the pre-requisites to migrate the general db to a Cassandra cluster, one of them is to have an Elasticsearch cluster available (Migrating the general database to a DMS Cassandra cluster | DataMiner Docs).
But if we check the supported architecture (Supported system data storage architectures | DataMiner Docs), it depicts a scenario of a FO pair with an external Cassandra Cluster with 3 nodes:
Is it really a pre-requisite, or just the recommendation?
Kind Regards
Hi Tiago,
An Elastic cluster is required if you want to migrate to Cassandra cluster as not all data (Alarms for example) is stored in the Cassandra cluster.
The picture you have is indicating to have 1 Cassandra (cluster) per failover pair. If there are multiple failover pairs, you would need multiple Cassandra (clusters)
The last image on that data storage architectures page is not showing the DM Cassandra Cluster feature, it’s showing 1 Cassandra (cluster) per DM node (pair). DM doesn’t care how many Cassandra nodes you have for a DM node, but in that scenario, you will need a separate Cassandra (cluster) per DMA pair.
Hi Matthijs,
Looking to the Data Storage Architecture page, it looks like ElasticSearch is required to have a Cassandra Cluster, not necessarily only for migration.
https://community.dataminer.services/data-storage-architecture/#:~:text=FeaturesrequiringanElasticsearchindexingengine
But then, when we check the Supported system data storage architectures on DataMiner Docs, looks like it’s possible to have a Cassandra Cluster without ElasticSearch involved.
It’s natural to assume that a requirement (ElasticSearch) needs to be always present, otherwise the feature (Cassandra Cluster) doesn’t work.