Distributed Cache Cluster Definitions File
The definitions.json file for the distributed cache cluster must define the following nodes:
-
Two data servers (role DM), configured as a mirror
-
Three application servers (role AM)
-
Load balancer for application servers
-
Arbiter node for data server mirror
This configuration is illustrated in the following:
Distributed Cache Cluster to be Deployed by ICM
The table that follows lists the field/value pairs that are required for this configuration.
Important:
A standalone InterSystems IRIS instance, nonmirrored or mirrored—that is, a DM node or two DM nodes forming a mirror—can be deployed with a standard license, as can a distributed cache cluster (DM node or mirrored DM nodes plus AM nodes). In all sharded cluster configurations, node-level or namespace-level and nonmirrored or mirrored, all nodes on which an InterSystems IRIS container is deployed require a sharding-enabled InterSystems IRIS license. For example, if a nonmirrored or mirrored standalone instance with a standard license has DS nodes added to it, the license used for all of the nodes must be upgraded to a sharding license.
| Definition |
Field: Value |
|
Two data servers (DM) using a standard InterSystems IRIS license, configured as a mirror because “Mirror”: “true” in shared defaults file.
Instance type, OS volume size, data volume size override settings in defaults file to meet data server resource requirements. |
"Role": "DM",
"Count": "2",
"LicenseKey": "ubuntu-standard-iris.key,”
"InstanceType": "m4.xlarge",
"OSVolumeSize": "32",
"DataVolumeSize": "150", |
|
Three application servers (AM) using a standard InterSystems IRIS license.
Numbering in node names starts at 0003 to follow DM nodes 0001 and 0002.
Load balancer for application servers is automatically provisioned. |
"Role": "AM",
"Count": "3",
"LicenseKey": "ubuntu-standard-iris.key”,
"StartCount": "3",
"LoadBalancer": "true", |
|
One arbiter (AR) for data server mirror, no license required, use of arbiter image overrides InterSystems IRIS image specified in defaults file.
Node is numbered 0006.
Instance type overrides defaults file because arbiter requires only limited resources. |
"Role": “AR”,
"Count": "1",
"DockerImage": "intersystems/arbiter:latest-em",
"StartCount": "6",
"InstanceType": "t2.small", |
A definitions.json file incorporating the settings in the preceding table would look like this:
[
{
"Role": "DM",
"Count": "2",
"LicenseKey": "ubuntu-standard-iris.key”,
"InstanceType": "m4.xlarge",
"OSVolumeSize": "32",
"DataVolumeSize": "150"
},
{
"Role": "AM",
"Count": "3",
"LicenseKey": "ubuntu-standard-iris.key”,
"StartCount": "3",
"LoadBalancer": "true"
},
{
"Role": "AR",
"Count": "1",
"DockerImage": "intersystems/arbiter:latest-em",
"StartCount": "6",
"InstanceType": "t2.small"
}
]
