As many IT pros know, the stability and long life of any platform is desired. The main reason for this is stability. Over time however, it becomes necessary to upgrade the platform, whether it be the hardware, operating system, application or other bits of glue that make your services work. I work with customers helping to determine migration strategies for services, applications and servers. Many times, the application is available on the new platform, so it is just a matter of testing, and off you go. However, what happens when the application is still in use but the platform is just too old to maintain?
Enter my latest “real-life” migration. I run SmoothWall as my main firewall product. I have used a variety of others, including pfsense and some other commercial products. None however, has been as simple and as easy to use as my SmoothWall system. I have been hacking over many years VMware support into the platform. It is based on its own “customized” Linux kernel and libraries, which makes it very hard maintain. Well, vSphere 4.1 finally broke the old system, and I was not able to use any drivers or kernel optimizations anymore.
Enter in my solution, SmoothWall on CentOS! Using some old UNIX tricks, I managed to fool SmoothWall into thinking it is running on its own Linux system. The base is CentOS 5.5. No recompiles or big changes needed. Many of us old UNIX hands know that you can make older UNIX binaries work in a chroot environment. This is wayyy before virtualization as we know it today. Fortunately, the Linux kernel ABI is very consistent, so, this trick works great! At my old employer I used to use this trick all the time to migrate old broken build platforms onto modern, supported operating systems.
So, what is old is new again! I even gain SMP, and the ability to use more memory! Welcome additions to my firewall!