When it came time for fleet tracking and management software provider Cadec Global LLC to rebuild its software as a Software as a Service (SaaS) offering, Cadec's chief architect, Heimir Sverrisson, knew it had to be deployed on Linux, not Microsoft Windows or a proprietary Unix flavor like Sun Microsystems' Solaris or IBM's AIX.
Cadec's old system, Mobius TTS, was a client/server application based on Microsoft Windows running SQL Server. From the outset, Windows was eliminated because of scalability concerns; it didn't scale well enough to be used as a mission-critical SaaS platform. "On system administration tasks and operations, it was cumbersome and hard to script, and as a platform, hidden registries were a nasty thing, and you couldn't move components across machines very easily," Sverrisson said.
In the testing process, Sverrisson also discovered that SQL Server, which runs only on Windows, was failing stringent scalability requirements. "We were moving from a customer-hosted system to SaaS architecture, so of course we had to scale an order or two of magnitude," he said.
While Windows was problematic, Unix worked well and was nearly impossible to differentiate from Linux feature- and performance-wise. Solaris and AIX had excellent software stacks and utilities for integrating advanced file systems and clustering options, but so did Linux, Sverrisson said.
"[Linux] has caught up with all of those great features that were once only available on Solaris and AIX. Of course, the main difference is Linux runs beautifully on Intel hardware or AMD or whatever you might have -- and of course, it runs great in 64 bit," he said.
Right OS, which DB?
Moving to a new SaaS model was as much about reducing Cadec's workload as it was about modernizing an application. As a client/server application, Mobius TTS, required each customer to have its own database and server that Cadec was continually asked to update, maintain and fix, Sverrisson said. .
Cadec's IT staff was suffering under the maintenance burden. "Our customers are in transportation, not IT," Sverrisson said. "When customers needed an upgrade, it could be as many as 50 computers on their end. From our perspective, we had to maintain 100 of these installations [across North America], and there was really no way to guarantee that every customer was getting the upgrades. We had customers calling in with old versions of the software looking for support," he said.
With Linux a lock, the issue became which database would work on it with the least amount of scripting and customization. Cadec's IT staff had two options: IBM's DB2 or Oracle 11g. With scalability in mind, Sverrisson established new checklists for system security.
"From a total-system perspective, we have multiple [customers], and some of these companies even compete with one another. It is very sensitive in that sense," Sverrisson said. "If the system made a mistake and you could see a competitor's data, we wouldn't be in a good spot," he said.
Separating and keeping data separate was high on the list, but that didn't mean Cadec wanted the new application, dubbed PowerVue, to consist of 200 different databases, each with its own maintenance responsibilities, as Mobius had. Oracle 11g addressed that issue, Sverrisson said, because its Virtual Private Database provided separation and security in a single system without a superfluous number of physical databases.
"Oracle allows the user to put data in the same table from different sources, and by default you have these security policies in place on the database. It's isolated. … My programmers don't have to put 'where' clauses on it to watch the data," he said.
Oracle Internet Directory impressed him with its single sign-on and compatibility features. "Single sign-on is carried across the middle tier onto the database. We could have a single sign-on proxy box with Apache running on Linux, and that can cross over to a Microsoft IIS running .NET that eventually comes back to Oracle on a Linux box," Sverrisson said. "Oracle allowed us to cross operating system boundaries. … We couldn't find that kind of coherent application from any other vendors."
That included IBM, with its DB2, which didn't meet any of Cadec's needs. DB2 didn't have the data isolation features found in Oracle, which would have meant building an access layer on top of it or embedding one in each query. DB2 also struggled with the potpourri of operating systems running in Cadec's data center: a service-oriented architecture platform built on Linux, Java-based Web applications running in .NET, and even some C. "This is the way systems are built today; in a single OS system you lose out," he said.
One service that Cadec did not buy from Oracle is support for Red Hat Enterprise Linux 4, or RHEL 4 , which Cadec used to house its database. In October 2006, Oracle announced the Unbreakable Linux program, which included steep discounts on Red Hat Linux support (as much as 50%). Customers can also download an alternative distribution called Oracle Linux, although that OS has not proven as popular as the support program.
This was a moot point for Sverrisson, however. Red Hat supported his organization just fine. "We are a pretty self-sufficient shop. We don't need much on the Linux support side of things. Mainly what we need is someone to provide us with software updates."
Migration tips and tactics
To build PowerVue, Cadec had to create a migration tool kit to help customers move from Mobius TTS to the new Linux-based system. The kit also allowed Cadec to transfer SQL Server data from the Mobius TTS hardware to a brand-new 64-bit HP BladeSystem with built-in Fibre Channel and two 1-Gbit Ethernet network switches. Sverrisson said he used Oracle Warehouse Builder to create the kit when the project began in the spring. The data migration has progressed "pretty painlessly" and should be completed sometime this fall, he said.
But because SQL Server schemas are different from Oracle's, Sverrisson and his team had to write new ones to complete the process. This meant additional work, but Sverrisson said it gave his team the opportunity to address and eliminate some "general database" and housekeeping issues in SQL Server.
Cadec is still migrating customers to PowerVue, although a majority of the project is in Sverrisson's rearview mirror. Specialized customers, such as those hauling pressurized gases, have taken longer to switch over given the sensitivity of their cargo and the fact that Mobius TTS is their mission-critical management system.
"With a journey like ours, the devil is in the details," Sverrisson said. "Other users should seriously understand their system before trying to go down a similar path; check out [your databases and operating systems] and make sure they're working seamlessly."
As with any migration, users should identify where the data bottlenecks could occur in each system and test and build a solution before a project begins, Sverrisson said.
Email Jack Loftus, News Writer, with your questions and comments on Oracle and Linux.