id

An identifier that you want to associate with the instance. Note the following:

• If the service that's specified by ServiceId includes settings for an SRV record, the value of InstanceId is automatically included as part of the value for the SRV record. For more information, see DnsRecord Type.

• You can use this value to update an existing instance.

• To register a new instance, you must specify a value that's unique among instances that you register by using the same service.

• If you specify an existing InstanceId and ServiceId, Cloud Map updates the existing DNS records. If there's also an existing health check, Cloud Map deletes the old health check and creates a new one. The health check isn't deleted immediately, so it will still appear for a while if you submit a ListHealthChecks request, for example.