Editor’s note: Terri Grauer is a consultant and writer specializing in the application of technologies to business challenges. Sanity Check is a regular feature in LTW.
_______________________________________________________________________________________With all the buzz about Service Oriented Architecture (SOA) in the media, it comes as no surprise that SAP has some pretty nifty solutions based on SOA.
What did surprise me, while doing my research, is how long some of these solutions have been available. Since November 2002 (before SOA was a buzz-word) SAP in conjunction with Fujitsu and Network Appliance have offered a solution called “FlexFrame for mySAP”.
The FlexFrame solution is designed to make mySAP independent of the physical hardware infrastructure required, creating a virtual environment for the enterprise resource planning (ERP) solution.
A little background about SAP R/3 installations (not based upon SOA). They are cumbersome and time-consuming to setup based on the distributed SAP architecture. Several servers are needed in the distributed model; one for the database, one for the application services, others for specific SAP services required for the distribution of services and workload balancing.
Historically each server must be built (hardware, drivers, etc.), an operating system loaded, storage assigned (if not internal) and then the SAP specific processes can be loaded. Each server is assigned a specific SAP task/role in this model and then the sum of the parts creates the complete SAP environment. Therefore a very rigid relationship is created between the physical server and the SAP components which reside on it — causing downtime for the associated SAP services and complications if a server has to be replaced.
A Virtual Solution
Using Service Oriented Architecture principals to build the infrastructure frees the SAP services from being tightly coupled with physical hardware. Rather, each service is assigned a virtual IP address and virtual hostname freeing it from the physical relationship. In the event a server takes a ‘dirt nap’ and needs to be replaced, the process is much quicker and smoother. Simply assign the virtual IP address and hostname to a new piece of properly configured hardware and the SAP services are up and running again. (Granted, the replacement hardware does need to be properly configured, which can take several hours if starting from bare metal.)
Another alternative is to point the virtual IP and hostname to an existing server, capable of carrying the additional workload, rather than bringing in new hardware.Two other requirements for this design to work properly are a central operating system for all SAP servers — (‘diskless’ servers booting from the SAN) and Network attached storage.
By running the operating system on a ‘central server’ which can be accessed by all application servers, the maintenance and support required by systems administrators is kept to a minimum. The network attached storage is used by all the servers in the configuration to avoid a ‘captive’ image residing on any one piece of hardware. This allows an SAP service running on an overworked (or dead) server to be stopped and restarted on another server in the environment, easily.
Some of the advantages of this SOA designed mySAP installation are:
For existing SAP installations considering the conversion to a service oriented architecture the process may be a painful one. However, with the impending SAP upgrades and/or conversions to mySAP, it might make considerable financial sense to investigate this design alternative as part of the upgrade path. I am certain you can find a nice NetAPP, Fujitsu or SAP presales engineer to assist you in the evaluation process.
Terri Grauer is a consultant and writer specializing in the application of technologies to business challenges. She can be reached via email at email@example.com