Our datacenter, your cloud – Message Hub on Bluemix Dedicated

Share this post:

At the end of last year, we released our new Message Hub service in IBM Bluemix. We began by offering the service in our Dallas and London datacenters, but the plan has always been to offer a wider range of options.

A multi-tenant, pay-as-you-go cloud service is very cost-effective, but it does mean that you’re sharing infrastructure with others. If you don’t want to mingle with the unwashed masses, what can you do?

The next step up in isolation is called Bluemix Dedicated. This is a single-tenant Bluemix environment hosted in a separate SoftLayer account managed by IBM. It’s like having your own cloud provisioned in an IBM datacenter. Many of the Bluemix services, including Message Hub, are available in Bluemix Dedicated.

Dedicated Message Hub for when you don’t want to share

So, what does a dedicated instance of Message Hub look like? Well, Message Hub is based on Apache Kafka. When you use Message Hub in the public cloud, you are sharing a Kafka cluster with other users. You get your own topics to keep your data separate but the underlying infrastructure is shared. You’re limited to what you can use and could find that the performance you achieve is limited or affected by other users.

In a dedicated instance of Message Hub, you actually get your own Kafka cluster with enough capacity for more demanding messaging workloads. There are no other users of your cluster. The Kafka cluster is deployed onto bare-metal machines entirely for your use. If your isolation requirements demand it or your throughput requirements justify it, a dedicated instance of Message Hub is an impressive capability but it is a big step up.

Billing for Message Hub for public versus dedicated

The way that billing works is very different. In public Bluemix, the cost for Message Hub is determined by two factors: the number of topics (partitions actually) that you use and the volume of messages you send and receive. There is no charge for message data while it is retained on the topics, but the data that each partition retains is capped at 1 GB.

In a dedicated instance of Message Hub, you pay for the service rather than how much you use it. You can have up to 75 partitions spread across topics as you choose, but we expect most users to have fewer even for the most demanding workloads. There still needs to be a limit for message data retained on the topics just to make sure the cluster doesn’t run out of space, so each partition is capped at 10 GB.

Accessing public services from Bluemix Dedicated via syndicated catalog

For users of Bluemix Dedicated who want to use Message Hub but cannot justify having a dedicated instance, there is another option known as syndication. Most services in public Bluemix can be used from Bluemix Dedicated, and this includes Message Hub. The syndicated Bluemix catalog contains services in the public Bluemix environment which can be accessed from within Bluemix Dedicated environments. This is a handy option if you need to use a service which isn’t yet available in Bluemix Dedicated or if a dedicated instance of a service is not appropriate for your anticipated level of use. Of course, an instance of a service selected from the syndicated catalog is actually in public Bluemix and doesn’t get the isolation benefits of a dedicated instance.


If you like the idea of Message Hub but need more performance or isolation, you should be thinking about a dedicated instance of Message Hub. You can read about Bluemix Dedicated here, or learn more about Message Hub from the Message Hub documentation.

More Community stories
May 3, 2019

Kubernetes Tutorials: 5 Ways to Get You Building Fast

Ready to start working with Kubernetes? Want to build your Kubernetes skills? The five tutorials in this post will teach you everything you need to know about how to manage your containerized apps with Kubernetes.

Continue reading

May 3, 2019

Using Portworx to Deploy and Manage an HA MySQL Cluster on IBM Cloud Kubernetes Service

This tutorial is a walkthrough of the steps involved in deploying and managing a highly available MySQL cluster on IBM Cloud Kubernetes Service.

Continue reading

May 2, 2019

Kubernetes v1.14.1 Now Available in IBM Cloud Kubernetes Service

We are excited to announce the availability of Kubernetes v1.14.1 for your clusters that are running in IBM Cloud Kubernetes Service. IBM Cloud Kubernetes Service continues to be the first public managed Kubernetes service to support the latest upstream versions from the community.

Continue reading