Starting DataStax Enterprise as a service
Steps for starting the DataStax Enterprise (DSE) service when DataStax Enterprise was installed from RHEL or Debian packages.
All nodes types are DataStax Enterprise nodes and run the database.
You can also use DSE OpsCenter to start and stop nodes.
Considerations for starting a cluster
Be aware of the following when starting a DataStax Enterprise cluster:
- Nodes must be segregated by datacenters
-
Transactional, DSE Search, DSE Analytics, and
SearchAnalyticsnodes must be in separate datacenters. For example, in a cluster with both DSE Search and transactional nodes, all DSE Search nodes must be in a one or more search datacenters and all transactional nodes must be in one or more datacenters.DSE Graph must be enabled on all nodes in a datacenter. It no longer has to be enabled on the entire cluster.
- Deploying a mixed-workload cluster
-
When deploying one or more datacenters for each type of node, first determine which nodes to start as transactional, analytic, DSE Graph only, DSE Graph plus other types, DSE Search, and
SearchAnalyticsnodes. Deploy in this order:-
Analytic seed nodes.
-
Transactional or DSE Graph only seed nodes.
-
DSE Search seed nodes.
-
SearchAnalyticsnodes. -
Remaining nodes one at a time. See Initializing multiple datacenters per workload type.
-
- DSE Analytics nodes
-
Before starting DSE Analytics nodes, ensure that the replication factor is configured correctly for the analytics keyspaces. Every time you add a new datacenter, you must manually increase the replication factor of the
dse_leaseskeyspace for the new DSE Analytics datacenter.
Start up options
Set the type of node in the /etc/default/dse file.
(Start-up scripts are also available in /etc/init.d.)
| Option | Description |
|---|---|
|
Starts the node as a DSE Graph node. |
|
Starts the node as a Spark node and starts the Spark master service. |
|
Starts the node as a DSE Search node. |
Transactional-only or BYOS nodes |
|
For example:
- Spark Analytics node
-
SPARK_ENABLED=1 SOLR_ENABLED=0 GRAPH_ENABLED=0or
SPARK_ENABLED=1No entry is the same as disabling the omitted type.
- Spark Analytics, DSE Graph, and DSE Search node
-
SPARK_ENABLED=1 GRAPH_ENABLED=1 SOLR_ENABLED=1 - BYOS (Bring Your Own Spark) nodes
-
For these nodes, Spark runs in separate Spark cluster from a vendor other than DataStax. To prevent the node from attempting to use the DSE integrated Spark, you must start BYOS nodes as transactional nodes. To do this, set all node types to
=0or omit them.For a combined DSE Graph and BYOS node, set the
GRAPH_ENABLEDoption to1only. Set all other types to0or omit them. - SearchAnalytics nodes
-
An integrated DSE SearchAnalytics cluster allows analytics jobs to be performed using Search index syntax.
SPARK_ENABLED=1 SOLR_ENABLED=1
Procedure
-
If DataStax Enterprise is running, stop the node.
-
Set the node type in the
/etc/default/dsefile as explained in Start up options. -
Start DataStax Enterprise:
sudo service dse startIf a
Timed out while waiting for DSE to starterror appears, see DSE cannot start with YAML parsing error. -
To verify that the cluster is running:
nodetool statusThe
nodetoolcommand shows the node type and the status. For a transactional node running in a normal state (UN) with virtual nodes (vnodes) enabled shows:Datacenter: Cassandra ===================== Status=Up/Down |/ State=Normal/Leaving/Joining/Moving -- Address Load Tokens Owns Host ID Rack UN 127.0.0.1 82.43 KB 128 ? 40725dc8-7843-43ae-9c98-7c532b1f517e rack1For example, a running node in a normal state (UN) with DSE Analytics without vnodes enabled shows:
Datacenter: Analytics ===================== Status=Up/Down |/ State=Normal/Leaving/Joining/Moving -- Address Load Owns Host ID Token Rack UN 172.16.222.136 103.24 KB ? 3c1d0657-0990-4f78-a3c0-3e0c37fc3a06 1647352612226902707 rack1
