Managing Entries in the Service Discovery Database to Enable Container Communication

You can view the DNS information recorded for running Docker containers in the Oracle Container Cloud Service Service Discovery database. This information enables containers to communicate with each other.

To view, update, and add DNS information for a service in the Service Discovery database using the Oracle Container Cloud Service Container Console:
  1. On the Service Discovery page of the Container Console, review the services currently registered in the Service Discovery database.
  2. Use the Services tab to:
    • View details for all current service entries in the Service Discovery database.
    • Manually add details for a new service to the Service Discovery database by clicking New Service and specifying options for the service entry:
      Option Use to specify:
      ID A unique identifier for this service entry in the Service Discovery database. For example, my-redis.

      Unique identifiers generated by Oracle Container Cloud Service are alphanumeric strings. For example, 85349d243fa7853fbe7516947916411bd3acec7380fb87049ebdbbde25d78a0d.

      The identifier maps to the DNS host name. You can’t change the identifier once you’ve saved the service entry.

      Name/Service The service to which the entry applies. For example, redis.

      To group multiple entries for the same service into a Round Robin DNS pool, specify the same name in this field for all the entries. For example, if you were creating an entry for the redis service, you might specify redis in this field for the first service entry and for all subsequent entries for the redis service.

      Address The IP address of the host or service. For example, 192.0.2.175.

      IP addresses of service entries that have the same name in the Name/Service field are added into a Round Robin DNS pool.

      Port The port on which this service can be attached. For example, 6379.

      Don’t append TCP or UDP to the port number because Oracle Container Cloud Service doesn’t differentiate between TCP and UDP.

      Tags One or more tags to assign to this entry. For example, redis_tag.

      Tags you specify here are only relevant in the Service Discovery database, and are not available as tags elsewhere in Oracle Container Cloud Service.


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    • Update existing service details by clicking Edit.
    • Remove details of a service from the Service Discovery database.
  3. Use the Key/Value tab to:
    • View keys and values for all current service entries in the Service Discovery database.
    • Manually add details for a new key and associated value in the Service Discovery database by clicking New Key/Value.
      Option Use to specify:
      Key A unique key for this service entry in the Service Discovery database.

      Unique keys generated by Oracle Container Cloud Service include the name and id of the deployed service. For example, apps/ redis-001-redis-001-20160823-173743-80/containers/85349d243fa7853fbe7516947916411bd3acec7380fb87049ebdbbde25d78a0d.

      Value The IP address of the host running the container, concatenated with the port exposed by the service. For example, 192.0.2.175:9000.
    • Update an existing key or associated value by clicking Edit beside the entry you want to change.
    • Remove details for an existing key and associated value from the Service Discovery database.