On the AIXchange blog I came across a link to an article stating that Linux is now on parity with AIX Unix, something people have been saying for at least 5 years now – each time, AIX proponents have been able to clearly show that AIX still had a clear advantage over Linux, though each time the advantage has been lessened.

This time, though AIXchange have given a number of reasons why AIX still leads over Linux, this time I don’t believe it’s true for the vast majority of users.

Firstly I’d like to say AIX I’ve used AIX ever since I left university, my first job was as an AIX sysadmin, and I don’t believe AIX is going anywhere fast – it’s a very stable, secure, high performance environment for people who need it.

Given that, I think after reading the article, I’d pretty much agree with it entirely. Sure, AIX has all the technology bits and pieces that Linux doesn’t have to the same level of maturity, but what business benefits do they provide over and above Linux?

In terms of IBM hardware and software support, IBM support Linux to the same level of AIX, on IBM system P (POWER), and system X (x86 hardware), you can go to IBM.com/linux and sign up for IBM’s Support Line for Linux, and get excellent quality support from IBM for your Red Hat and Novell Linux systems.

For the technical benefits around the excellent AIX LVM and other disk management tools like mksysb, NIM, savevg, and alt_disk_install, these are all fantastic but have largely been made irrelevant in the x86 world by the advanced virtualisation options available. Whether you use the commercial VMware vSphere, or the open source KVM option, you can do online snapshots, rollback, clone, and backup your entire Linux systems in ways above and beyond what AIX can do with PowerVM.

Mentioning virtualisation, yes PowerVM is rock-solid and can scale to great heights, it’s currently falling behing vSphere when it comes to both features and management tools, and the only outstanding feature it has over vSphere is the ability to scale from a machine from a fraction of a processor through to 32 processors without downtime or significant performance overhead (vSphere has a maximum of 8 vCPUs at the moment).

And that to me is the only area where AIX currently beats Linux – if you need a machine with more than 8 processors (not cores), and more than 255GB of RAM, then I would pick AIX every time, but other than that I would strongly recommend a Linux server running on top of VMware vSphere.