Recommended Cherwell Service Host Scaling Configurations
Cherwell recommends the following deployments and configurations to horizontally scale the various components of CSM.
The configurations described below do not apply to hosted environments that use the Cherwell Service Host to run a local Scheduler.
Single-Node Configuration
In this typical CSM server installation, all Cherwell components are on a single machine and do not require horizontal scaling considerations. However, individual services scale vertically automatically. By default, each of the scaled services vertically scale when more work is enqueued then can be dequeued with the current resources.
To set up a single-node configuration, the Cherwell Service Host component is installed on a new machine. After the installation is complete, Cherwell Service Host is configured to communicate with the Application Server and the Cherwell Message Queue Service.
Full-Node Scaling Configuration
When the original installation can no longer handle the rate of work enqueued by CSM, and the original node can no longer vertically scale, then you should scale the system horizontally. The most straightforward way to horizontally scale CSM is to create a new full node.
In this configuration, the Cherwell Service Host component is installed on a new machine. After the installation is complete, Cherwell Service Host is configured to communicate with the Application Server and the Cherwell Message Queue Service from the first node.
Single-Service Separate Node Partial Scaling Configuration
Individual components of the CSM infrastructure may become overwhelmed as a company’s domain-specific business logic is implemented. In these cases, the CSM installation can be a single service at a time to help accommodate the workload.
In this scenario, the original installation is no longer able to keep up with the mail delivery workload and must scale. To accommodate a large amount of mail that needs to be delivered, a new instance of Cherwell Service Host is installed on a new server. The server is configured to communicate with the Application Server and the Cherwell Message Queue Service that is installed on the first node. Cherwell Service Host manages all services except for Mail Delivery Service, which is disabled.
Single-Service Separate Node Full Scale Configuration
In more advanced scenarios, CSM is scalable on any combination of services that are active on any number of nodes. While the options of scaled services are almost endless, a few rules must be maintained. One example configuration of CSM at scale is a single service per node.
In this configuration, the Cherwell Service Host component is installed on three new machines. After the installation is complete on each of the machines, Cherwell Service Host is configured to communicate with the Application Server and the Cherwell Message Queue Service from the first node. With communications configuration complete, each of the four Cherwell Service Host systems are configured to enable only a single service, one on each box.