posted on Thursday, July 22, 2010 11:56 AM
With the release of the F5 Management Pack v2.1.2 (available for download here) the F5 Application Designer extensibility framework has been updated to support various load-balancing scenarios, based on health and performance monitoring conditions of the applications monitored in System Center Operations Manager (SCOM).
1. The F5 Application Designer Extensions: a Quick Overview
The F5 Application Designer Extensions are application specific management packs built on top of the core F5 Management Pack. They provide holistic monitoring and auto-configuration support for various server platforms and application environments fronted by F5 devices (such as IIS 7, SharePoint 2007/2010, VMM Server 2008/R2). The traditional way of monitoring all these applications in System Center Operations Manager usually would be mostly scoped to the individual platform itself rather than a unified health monitoring view of the whole application environment.
Here’s where the F5 Application Designers come into play and wire the applications together into a unified health monitoring diagram, as “Application Instances”, enabling a more comprehensive view of the applications’ health in System Center Operations Manager.
With the F5 Application Designer extensions, the F5 LTM Pool Members are paired with their related application components (such as Windows servers, Web servers, Virtual servers, SharePoint servers, etc) and the resulting object hierarchies are wired together as “Application Instances” grouped within an “Application Instance Group”, which ultimately is paired with the related F5 LTM Virtual Server, making up the “Overall Application” monitoring object. Such an application can be for example the entire deployment of an e-commerce web-farm, monitored within System Center Operations Manager.
The health of the App Instance by default represents the worst health of any of it's member components. In turn, the overall Application's health depends on at least one of the App Instances being healthy as well as the health of the underlying LTM Virtual Server.
More information on F5 Application Designer Extensions related topics can be found here:
2. Load Balancing Scenarios
With this article we initiate a series of presentations centered around various Data Center Orchestration scenarios, where the F5 App Designer extensions not only help with the overall health monitoring of a complex application environment, but also provide automatic intelligent decisions based on certain health and performance monitor triggers.
Here's a brief overview on some of these scenarios (use cases).
2.1. Health Based Load Balancing (Scenario #1)
Description: Enable / Disable LTM Pool Member based on application specific health-monitor state change
Use Case:
- Trigger an Error health-state for an IIS 7 specific monitor (IIS 7 Application Pool) by stopping the Default Application Pool on the IIS Server hosted on LTM Pool Member 1
- See the related (hosting) App Instance health state turn red / Error
- See the related LTM Pool Member (1) health state turn red / Error
- Load balancing follows LTM Pool Member 2
- Resume the Success health-state for the IIS 7 monitor (IIS 7 Application Pool) by starting the Default Application Pool on the IIS Server hosted on LTM Pool Member 1
- See the related (hosting) App Instance health state turn green / Success
- See the related LTM Pool Member (1) health state turn green / Success
- Load balancing follows LTM Pool Members 1 and 2.
2.2. Performance Threshold Rule Based Load Balancing (Scenario #2)
Description: Enable / Disable LTM Pool Member based on application specific threshold rules
Use Case:
- Create a unit monitor based on an IIS 7 specific rule (ASP.NET\Worker Process Restarts Performance Rule), targeting the ASP.NET Application Pool object
- Create the ASP.NET worker process recycle condition based on the number of requests made
- The unit monitor created above will mark the health of the ASP.NET Application Pool object's state as red / Error
- See the related (hosting) App Instance health state turn red / Error
- See the related LTM Pool Member (1) health state turn red / Error
- Load balancing follows LTM Pool Member 2
- Resume the Success health-state for the unit monitor by lowering the number of requests and having the ASP.NET worker process recycle no more
- See the related (hosting) App Instance health state turn green / Success
- See the related LTM Pool Member (1) health state turn green / Success
- Load balancing follows LTM Pool Members 1 and 2.
2.3. Performance / System Metrics (Provisioning) Based Load Balancing (Scenario #3)
Description: Update LTM Pool Member load-balancing ratios based on system-performance / provisioning
Use Case:
- Set the load-balancing method for the targeted LTM Pool to “Ratio (member)”
- Start by setting the Ratio on both LTM Pool Members to 1
- Provision LTM Pool Member 1 (virtual machine) with 2GB of RAM
- Provision LTM Pool Member 2 (virtual machine) with 4GB of RAM
- See how the load balancing ratios on LTM Pool Member 1 and LTM Pool Member 2 get updated (automatically) to 33 and 67 respectively, following the capacity (total memory) of the LTM Pool Members
Details on configuring and running these use cases will follow in subsequent articles, so stay tuned.
