As a final preview of this week's building block sessions in the Enabling cloud computing with WebSphere campaign, I caught up with WebSphere DataPower architect Tim Smith. Tim is delivering a podcast that introduces and explains the new Application Optimization capabilities in the WebSphere DataPower line of products. Here is what Tim had to say:
Me: I speak with quite a few customers about the WebSphere CloudBurst Appliance, and for once I'm happy to be the one asking this question. Why do we deliver WebSphere DataPower in the appliance form factor?
Tim: DataPower has become a dominant player in the DMZ and in the ESB. Much of the reason is that this is a purpose built hardware appliance. There are many things that our customers like about this appliance package. First, it has security as part of its DNA. The basis for securing connections, applies throughout the network whether it is in a DMZ or in an ESB. The physical box provides tamper resistant protection. Another reason is availability -- there are no spinning media, dual power supplies, and a focus on fail over support.
In both the DMZ and the ESB, there has been a proliferation of products. The main reason for the proliferation is that customers want to remove as many decisions from the general purpose server as possible, and let servers do what they do best, process application requests. The devices that have been proliferating make more decisions on the request. They do deep packet processing and routing. They also may transform the request into an entirely different request. So, there are an abundance of "pre-processing" decisions and operations made. With DataPower, many functions are integrated into the single hardware platform, giving you a smaller box count. No need to purchase and maintain several platforms, their OS and software versions, compatibility lists, etc. With a single hardware box that does so many things, we can greatly reduce the total cost of ownership for our users.
The DataPower appliance is a blend of Hardware and firmware that is well provisioned with hardware assists that help compile, parse, and assist in many of the intensive packet processing capabilities. To summarize, you get an extremely flexible and adaptable product that reduces total cost while increasing performance.
Me: A theme that comes up in cloud computing over and over is consolidation. Can you speak to the consolidation offered by WebSphere DataPower appliances with respect to the self-balancing capabilities?
Tim: Yes. My answer to the prior question was a long-winded way of describing DataPower's ability to consolidate many features into a single platform. Self-balancing is an example. As DataPower became more popular, larger installations required multiple DataPower appliances in a tier of platforms. A common architecture was to place a load balancer or IP sprayer in front of the tier to distribute the traffic evenly among the tier of DataPower appliances. An IP sprayer is an example of another platform that needs to be added to the environment. It is another box that must be purchased, managed, and maintained. Self-balancing is a feature that was added to DataPower to eliminate the need for an IP sprayer. The way it works is that one of the DataPower appliances in the tier owns the Virtual IP (VIP) Address. It receives all of the traffic, and then distributes it to each of the other DataPower appliances in the tier. If the DataPower appliance that owns the VIP address goes down, one of the others is elected and it takes over. The result is one less product required to support the same level of functionality.
Me: For much of the past, cloud computing mostly focused on virtualization and management of resources at the raw compute level (servers, storage, networking, etc.). While there is definitely ongoing focus here, we start to see it moving up the stack towards applications, and part of that effort includes more evolved application load distribution. With that in mind, how can WebSphere DataPower help users more effectively distribute requests to their applications?
Tim: If a front end appliance or gateway device can dynamically learn information about its environment, specifically the back end, it will be able to make better decisions on how and where to route the request. This is one of the tasks that the Application Optimization feature addresses. Information from the back end can of course be manually configured, but the real value in cloud computing is dynamically adapting when new server resources are brought on line or are taken off line. In the 3.8.0 release, we implemented something called Intelligent Load Distribution (ILD). Intelligent load distribution focuses on continually learning the topology of a back end, updating DataPower's load balancers with that information, and distributing the load based on the updates. In addition to the topology, ILD learns the weights associated with each server. These weights can continually and automatically change as traffic patterns change. The result is load balancing to the back end that sends the optimal amount of load to each server.
Another traffic distribution aspect incorporated into ILD is session affinity. When a server application needs to receive every request from a given client, session affinity is used to route the requests to the same server. In some sense, session affinity overrides the load balancing algorithm. The session affinity support works with any type of back end server, but with a WebSphere back end, all session affinity information is automatically configured.
Me: Continuing on the theme of application intelligence, what is this new Application Routing option in WebSphere DataPower?
Tim: ILD focused on learning the topology of the network and making better decisions based on an ever changing cloud topology. Application Routing does something similar by learning which applications are running on each server. Once a request is handed to DataPower's load balancer, the request is classified as to the application that it is targeted for. Then the request is load balanced amongst the servers that are running that application. The information to perform application routing is dynamically learned and changes as applications are added or removed.
WebSphere has invested substantially in managing the life cycle of an application. Changing from one edition of an application to the next sounds like an easy task, but it can be very difficult to perform this type of maintenance on a production environment. The DataPower appliance supports life cycle management by working with the WebSphere back end to provide group and atomic edition rollout. The rollout feature allows traffic to be gracefully diverted from servers that are being taken offline and reloaded with the new application edition. This rollout can be done while leaving the other applications on the server unaffected. This support makes edition rollout a very simple task for the system administrator.
When it comes to provisioning and managing WebSphere application environments in a cloud, nothing approaches WebSphere CloudBurst in terms of expertise and instant value. However, I bet there is more to your data center provisioning and management activities than just WebSphere application environments. You probably deploy and manage a wide variety of both IBM and non-IBM software. While some of these activities may be beyond the scope of the WebSphere expertise you get with WebSphere CloudBurst, they fall well within the reach of offerings from IBM Tivoli.
One of the Tivoli offerings that comes to mind in the service delivery automation arena is the Tivoli Service Automation Manager (TSAM). TSAM delivers capabilities to request, deploy, monitor, and manage a broad range of IT services within a cloud environment, in large part by using both virtualization and automation as delivery vehicles. Even better for WebSphere users, you can integrate TSAM and WebSphere CloudBurst to make use of TSAM capabilities in concert with the WebSphere deployment and management expertise delivered by WebSphere CloudBurst. When using these two together, you actually deploy and manage WebSphere CloudBurst patterns directly from the TSAM user interface.
The integration starts by providing information about a target WebSphere CloudBurst Appliance (essentially the location of the appliance and login credentials) within TSAM. After that, you run a discovery process included with TSAM to gather information about patterns on the target appliance. Once you discover the pattern information, you perform one last configuration step, and you are ready to go.
As far as actually initiating a pattern deployment, it works much like other project requests in TSAM. From the TSAM user interface, you create a new project based on a WebSphere CloudBurst pattern. The request goes into the queue, where an administrator can approve or reject the request. This gives a nice touch of workflow governance to WebSphere CloudBurst deployments. If approved, the project request proceeds and TSAM, by way of the WebSphere CloudBurst REST APIs, initiates the deployment of the selected pattern from the appliance. Of course, there is also a means to remove the virtual system directly from the TSAM user interface. You can cancel any WebSphere CloudBurst based project, and if approved by an administrator, TSAM again leverages the WebSphere CloudBurst REST API to trigger the deletion of the virtual system.
The integration of TSAM and WebSphere CloudBurst provides the best of both worlds really. You can use a single portal as a gateway for provisioning and managing a broad range of IT services within a cloud environment, while still leveraging the significant out-of-the-box know-how and value provided by WebSphere CloudBurst for WebSphere environments. Check out a demo of this integration here, and as always, let me know if you have any questions or comments.
Next up on our sneak preview of the building block sessions for the Enabling cloud computing with WebSphere campaign is the Dynamic Infrastructure Services block. One portion of that block is a discussion about some of the technical capabilities of WebSphere Virtual Enterprise given by Nitin Gaur. Nitin is a Consulting IT Specialist within WebSphere, and an all-around WebSphere guru. I caught up with him to ask a few questions about his upcoming podcast.
Me: When people think cloud computing, one of the core concepts is 'on demand'. They want just enough resource at just the right time. In that sense, can you tell me a little about the On-Demand Router (ODR) in WebSphere Virtual Enterprise (WVE)? What is it and what core functions does it provide?
Nitin: So, first allow me to take a step back. In my view, cloud computing is a new consumption and delivery model nudged by consumer demand and continual growth in internet services. I classify any Cloud computing platform exhibits the following 6 key characteristics:
Standards based delivery
Usage based equitable chargeback
I thus, deliberately use the term platform in the context of a cloud computing environment that facilitates flexibility, robustness and agility, as a systemic approach in providing a stage to hosting applications without the concern for availability or provisioning of underlying resources. Since hardware and software virtualization do offer significant cost and resource management advantages, it is not rare to see virtualized platforms as core building blocks of any cloud platform. Such virtualization technologies provide an elastic infrastructure service. In this respect, WVE provides application server virtualization, which enables an elastic business-policy-driven application infrastructure.
Now back to the On-Demand Router. The ODR is the autonomic engine that drives the activity enabling the elastic infrastructure discussed above. The ODR operates in a highly dynamic WVE environment, so it is imperative for the ODR to be aware of any changes in the environment such as newly deployed applications, the addition of new application servers, and any planned or unplanned server outages. It achieves this awareness by continuously interacting with WVE's fluid and dynamic feedback mechanism.
Me: Autonomic capabilities seem to be a core part of WebSphere Virtual Enterprise. To that end, can you tell us a little about the autonomic capabilities provided by dynamic clusters in WVE?
Nitin: Dynamic application placement is a defining capability of WVE that directly contributes to WVE's ability to provide a dynamic, virtualized, and goal-oriented environment for workload management and continuous availability. The dynamic application management capability maximizes the efficient use of hardware resources by allocating resources appropriately per application based on fluctuating demands in the enterprise infrastructure. It determines which servers to stop and start in a dynamic server cluster in order to meet current demand for applications, and it does this in the context of a set of administrator-defined policies that uphold the enterprise’s service level agreements (SLAs) for its application infrastructure. The dynamic application placement framework must balance resource availability against health policies, service policies, and the importance levels assigned to applications.
Dynamic server clusters are key to WVE’s ability to dynamically adjust the application environment according to server load, and they provide the basis for a virtualized server runtime environment. The big difference between a dynamic cluster in WVE and a static cluster in WebSphere Application Server is that dynamic clusters grow and shrink as needed to meet current demand by starting and stopping members of the cluster. Although dynamic clusters and static clusters can co-exist in a cell, dynamic application placement can only work with dynamic clusters. To prevent unchecked growth, each dynamic cluster has a mechanism that you use to define a boundary for that cluster’s growth. The boundary is both quantitative (based on criteria that define the minimum and maximum number of application servers that can run in the cluster simultaneously) and locational (based on criteria that confine the growth of the dynamic cluster to a defined set of nodes).
Me: I know you have been around the country, and for that matter globe, helping our users to adopt and implement WebSphere Virtual Enterprise. Tell us about one of your favorite customer stories.
Nitin: So I would cite an example of one of the leaders in the entertainment Industry (and my favorite customer), let's call them Company X (since I cannot cite the name). The core of the company's application infrastructure system is the Sales App Infrastructure (SAI) consisting of more than 10 enterprise applications. To keep up with demand, Company X was required to procure more hardware and software to support the core systems. This strategy resulted in a large infrastructure footprint with low hardware utilization. The increase in hardware footprint became difficult to manage and required additional resources. The large footprint of the company's deployment put them in reaction mode rather than a posture of proactive monitoring. Some application servers rendered themselves unavailable and required the team to restart them every 24 hours. From a cost standpoint, it costs the company the same amount of money to request a virtual platform as it would to purchase a new physical server. This led to significantly under utilized hardware throughout the enterprise. WVE was brought in to Company X to help better manage their WebSphere Application Server footprint. Dynamic clusters, application health policies, and application editioning features helped the company to better utilize hardware, reduce hardware expenditures, increase visibility into their applications, and improve availability of their applications.
In addition to helping with the existing environment, WVE helped Company X to roll out a new project with applications that required continuous availability to worldwide users. The team made use of policy-based workload management to ensure performance and availability levels of these new applications met their business needs. In addition, the company was able to reduce the amount of WebSphere Application Server licenses and physical servers required for this new deployment. In sum, WebSphere Virtual Enterprise saves the company significant time, money, and management effort.
When you build application environments in WebSphere CloudBurst, there are three main elements that comprise those environments: virtual images, patterns, and script packages. It is likely that at some point you will want to export your environments from a particular WebSphere CloudBurst Appliance. This may be in order to apply version control techniques, share resources among multiple appliances, backup business-critical files, or any number of other reasons. Whatever the reason, WebSphere CloudBurst provides the necessary facilities to support both image and pattern export. WebSphere CloudBurst provides export capability for virtual images that you can access via the web console and CLI. In addition, when you download the CLI from the appliance, you get a sample script called patternToPython.jy that you can use to facilitate pattern export.
The patternToPython.jy sample produces a script that you can use to recreate the targeted pattern on an appliance of your choosing. However, before running the script to recreate the pattern on an appliance, you must ensure that any images and script packages referenced by the pattern exist on the target appliance. Since WebSphere CloudBurst enables you to easily export and import virtual images, all you have to do is account for script packages when attempting to export complete application environments from WebSphere CloudBurst. While the appliance does not directly provide the means to export script packages like it does for images and patterns, the WebSphere CloudBurst Samples Gallery includes a sample that does. You can find this sample in the CLI scripts section of the samples gallery, with the title Export a script package in a portable format.
After downloading the sample CLI script, you simply unzip the archive and use the embedded Jython script from the WebSphere CloudBurst CLI with the following command:
This command will create a ZIP file containing the contents of the script package specified by SCRIPT_PACKAGE_NAME. In addition to simply copying the contents of the specified script package into the new ZIP file, the command will trigger the creation of a cbscript.json file based on the definition of the target script package. This file defines the properties of the script package such as the execution command, command arguments, etc., and the exportScriptPackage.jy script adds it to the newly produced ZIP file.
The result of using this sample is a self-contained ZIP file that you can load into any other WebSphere CloudBurst Appliance. Since the ZIP file includes the cbscript.json file, when you load it into another appliance you do not have to define any of the properties for the script package. This eliminates the potential for definition errors as you move script packages from one appliance to the other and makes it simple to export/import script packages among appliances.
There are a couple of things about the sample worth mentioning. First, if a cbscript.json file exists in the specified script package, the export script will not create a new one. Instead, the sample simply copies the existing one into the new ZIP file. Second, the target script package's contents must be a ZIP file. That is to say, the file associated with the script package in WebSphere CloudBurst must be a ZIP. If you are using anything prior to WebSphere CloudBurst 2.0, this is not an issue since you can only associate ZIP files with script packages. However, WebSphere CloudBurst 2.0 allows you to associate any type of file (ZIP, shell script, python script, etc.) with a script package.
If you are looking to effectively export all of the components of your WebSphere CloudBurst patterns, check out this sample script. I think it will make the process a bit easier for you. As always, comments and feedback are welcome.
I wanted to take a brief moment to remind you that the Enabling cloud computing with WebSphere campaign is well underway. Check out the various presentations and podcasts on solutions such as WebSphere Virtual Enterprise, WebSphere CloudBurst, Cast Iron Systems, WebSphere DataPower Application Optimization, WebSpan Integration as a Service Cloud, WebSphere Application Server Feature Pack for Dynamic Scripting, and more. All you have to do is navigate to the site, and you can download presentations or listen to audio/video replays at your convenience.
In addition to the podcast sessions, I want to point out a couple of upcoming events. The first is a live Q&A webcast that takes place next Thursday (9/23). Myself and other IBMers will be joining the webcast to answer your questions about cloud computing and WebSphere solutions. You can register to attend the session here, and you can submit questions ahead of time here.
A week after the live Q&A webcast (9/30), there will be an online JAM. Think of this as an online chat between IBMers and you, our users. You can ask questions, give us your feedback and suggestions, or just watch the proceedings. Like with the live Q&A webcast, you can submit questions ahead of time by navigating here.
I hope you are getting a chance to take advantage of some, or all of the campaign. Of course, you do not have to wait for the sessions to ask questions or give feedback. You can always leave a comment here or reach out to me on Twitter (@damrhein). Happy Friday!
Yesterday, we kicked off a WebSphere in the Clouds campaign designed to connect you with IBMers that can help you to leverage WebSphere solutions to build clouds. The campaign consists of webcasts, podcasts, live Q&A sessions, and online JAMs. You can listen to replays and sign up for upcoming events by visiting the Global WebSphere Community website.
Next week, the campaign delivers a series of podcasts that discuss the WebSphere technologies that form the building blocks of clouds. These podcasts will discuss both the business and technical aspects of these solutions, and they will cover topics like application infrastructure in the cloud, policy-based workload management using application virtualization, hybrid cloud integration, and more. Over the past few days, I had the opportunity to catch up with the various presenters of these podcasts to ask them a few questions about their solutions. These interviews provide a nice sneak peak at what is coming in the podcasts, and I will be posting them here in the coming days.
To kick things off, I'm posting a video interview with Marc Haberkorn. Marc is the WebSphere Product Manager for WebSphere CloudBurst, WebSphere Application Server Hypervisor Edition, and WebSphere Virtual Enterprise. My colleague, Ryan Boyles, caught up with Marc and got his thoughts on how these solutions enable virtualization and automation for your cloud environments. Enjoy!
I point this out about script packages because recently I put one together that is not a WebSphere Application Server administration task, but does provide configuration logic common to many WAS deployments. Specifically, I put together a script package that configures an IBM HTTP Server to be a reverse proxy server. This of course, allows clients to send requests to the IBM HTTP Server and have those requests pass through to a specified back-end destination (i.e. a service hosted on WebSphere Application Server) based on URI paths.
The script package is not all that different from many of the ones I put together. It contains a shell script (which provides configuration and orchestration logic) as well as a cbscript.json file that defines the script package's characteristics when I upload it into WebSphere CloudBurst. The notable difference in this script package is that I include a Perl script that modifies the IBM HTTP Server configuration file. This just reiterates the point that you are not limited to only wsadmin and shell scripts within your script packages.
The workings of the script package are quite straightforward. It starts with a call to the shell script that modifies the IBM HTTP Server's configuration file to ensure the loading of a couple proxy modules:
sed -i s/"#LoadModule proxy_module modules\/mod_proxy.so"/"LoadModule proxy_module modules\/mod_proxy.so"/g $HTTP_CONF
sed -i s/"#LoadModule proxy_http_module modules\/mod_proxy_http.so"/"LoadModule proxy_http_module modules\/mod_proxy_http.so"/g $HTTP_CONF
As you can see, the createProxy.pl script accepts a single argument. This argument represents the reverse proxy configuration information provided by the user during deployment. The Perl script parses the single argument and creates the appropriate proxy directives in the IBM HTTP Server's configuration file:
After the invocation of the script above, control returns to the shell script. The shell script restarts the IBM HTTP Server so that the configuration changes take place. The result is an up and running IBM HTTP Server acting as a reverse proxy based on information supplied during deployment. The listings here do not show the full script package, but I hope to have it up on our WebSphere CloudBurst Samples Gallery soon.
If the script above provides some configuration logic you can use, that is good. However, my main point for bringing it up here is to point out that WebSphere CloudBurst script packages can be more than shell and wsadmin scripts that perform WebSphere Application Server configuration tasks. You can use them to do any sort of scripted activity that is essential to your application middleware deployment process. Happy scripting!
The concepts that govern users and user groups in WebSphere CloudBurst are fairly basic, but I get asked about them enough that I believe they warrant a short discussion. First things first, you can define users in WebSphere CloudBurst and optionally define user groups to assemble users into logical collections. For both users and user groups, you can assign roles that define the actions a particular user or group of users can take using the appliance.
All of that is straight forward, but it can get a bit tricky once we start considering the effects of user permissions when managing at the user group level. The basic premise is that when a user belongs to a group or groups, the user's effective permissions are a sum of the permissions to all of the groups to which they belong. While that is easy to say, and maybe even to understand, I feel like an example always helps.
Consider that we have a single user WCAGuy that belongs to the PatternAuthors, ContentCreators, and CloudAdmins groups. The permissions for those groups are as follows:
PatternAuthors: Users in this group have permission to create and deploy patterns
ContentCreators: Users in this group have permission to create catalog content as well as create and deploy patterns
CloudAdmins: Users in this group have permission to administer the cloud, create catalog content, and create and deploy patterns
Naturally then, it follows that the WCAGuy user can administer the cloud, create catalog content, create patterns, and deploy patterns. So then, what happens if we remove the WCAGuy user from the CloudAdmins user group? Well, as you may expect, there is an update to the user's permissions. The WCAUser user can no longer administer the cloud, but they can still create catalog content, create patterns, and deploy patterns (owing to their membership in the other two groups). Similarly, if we next removed the WCAGuy user from the ContentCreators group, then the user would retain only the permission to create and deploy patterns.
Just one more thing, let's talk about what happens when I remove a user from a group and they no longer belong to any groups. Consider that I created the WCAGuy user with the permission to create catalog content as well as create and deploy patterns. Next, I added the user to the CloudAdmins group, meaning the user now has the permission to administer the cloud. I promptly decide that the user has no business with those permissions, so I remove the user from the CloudAdmins group. What happens? The user retains the permission set of the last group to which they belonged. In this case, that means the WCAGuy user retains cloud administration rights. I have to update the user's permission set if I want to take that right away, but in this case, it will not automatically disappear upon removing them from the CloudAdmins group.
I hope this helps clear up any ambiguity you may have had concerning users, user groups, and permission sets in WebSphere CloudBurst.