Virtualization is a standard practice for IT shops around the world. However, as more data center operators look to consolidate and migrate to new virtualized environments, some legacy applications remain stumbling blocks on the way to a 100% virtualized infrastructure.
Legacy apps are tough nuts to crack: your users are accustomed to them, so they are highly efficient in business use, but they might clash with your more modern IT tools, they might no longer supported by the vendor, or the hardware underneath might be ready to kick the bucket.
“No worries,” I hear you say. “I can just virtualize the platform.”
That might work in most cases, but there are some legacy apps that either just won’t make the leap to virtualization or are too much trouble to virtualize to make it worthwhile. Here are the most common examples run into by our techs:
It’s possible to virtualize Oracle databases, but performance concerns have led many administrators to be apprehensive about it. Generally you’ll find an additional 15-20% increase in IOPS performance and disk bandwidth is possible with native workloads vs. VMware virtualized Oracle databases. Top performance I/O storage systems might be necessary to reach performance parity.
Oracle licensing costs aren’t likely to be reduced through virtualization, and their complicated licensing model makes it hard to sort out the final costs ahead of time.
Some legacy application require USB dongles to be plugged in to servers in order to verify software licensing and activate the software. This can be impossible to replicate in a virtual environment, even with USB support.
There is third party software that can work around this for some applications, but if your app requires USB dongle verification, make sure to check with your vendor before purchase. If so, look for USB over Ethernet solutions that support x64, have signed drivers, and support the operating system. There are also USB Anywhere products that connect a USB hub to the network (AKA USB over IP).
Even if you get this to work, you’ll need to be careful in managing USB over Ethernet. Thorough testing, consistent server/client software versions, IP filters…there are many considerations. If your platform is reliant on USB, even with a USB over IP device that keeps your VMs free, it can cripple any disaster recovery plans. If the site with your USB dongles is offline, you’re SOL at the recovery site unless you have backup licensing or other dongles.
Your software vendor might have caved and offers a new version with a software key instead of USB hardware verification. If so, congrats! An upgrade and you can virtualize.
Virtualization platforms can’t support every legacy platform, unfortunately. Some common legacy systems are HP-UX and IBM AIX and AS/400, circa late 1990s and early 2000s. VMware doesn’t support these platforms, even though they go way back for Linux and Windows OS. Until the applications running on these platforms are rebuilt, clients who want to virtualize must remain on physical infrastructure.
IBM AIX runs on Power architecture, not x86, and can only be virtualized through IBM PowerVM. Most HP-UX machines are not likely to be on x86 servers, either, meaning you must use HPVM – Integrity Virtual Machines.
What bumps in the road have you hit when trying to virtualize legacy platforms and applications? Do you know any workarounds for these examples, or do you have some additional legacy apps that won't run on VMware or Hyper-V?