Don’t Use An SMP Kernel When Virtualising FreeBSD 6.4 On VMWare ESX/ESXi

One of my clients has some FreeBSD 6.4 installs on hardware that is slowly dying and asked me to virtualise them onto an HP ProLiant ML350 G5.

The HP ProLiant had been running a Windows Server 2003 VM and a Windows Server 2008 VM on top of a Windows Server 2008 Core install with Hyper-V reliably, but these VMs were no longer in use and surplus to requirements.

I blew away the Windows Server 2008 Core install and installed VMWare ESXi 4.0 with the HP customisations. I then installed FreeBSD 6.4, copied across all the data from the physical install and proceeded to build the required ports.

This is where all the problems started. Random signal 11 crashes started occurring throughout this build process.

So I quickly created a new VM and installed FreeBSD 7.3 to it. Again, installation was no problem. Copied across all the data and successfully built all the ports. Only problem is the servers in question run an old Linux binary. This binary would start up successfully but would not accept any network data. Changing the linux_base port from the old RedHat 7.3 one to the current Fedora Core 4 one made no difference.

At this point I walked away and went to bed. By morning I had worked out what the problem was, so I went back to my FreeBSD 6.4 VM, reduced the number of vCPUs to 1 and swapped the SMP kernel for the GENERIC one. All ports then built successfully. The VM in question is now being stress tested for any problems prior to production use.

Moral of the story? Even though your virtualisation stack may support the Guest OS in question, it doesn’t mean that your Guest OS won’t necessarily have problems when virtualised. Perform burn-in/stress tests prior to production use.

The only reference I could find to related problems was on the FreeBSD-stable and FreeBSD-bugs mailing lists:

FreeBSD-stable: Failure to make world for RELENG_6_4

FreeBSD-bugs: misc/133264

Windows Server 2008 Standard Edition - License Change Regarding Virtualisation

The introduction of Hyper-V to all editions of Windows Server 2008 (except Web Edition) has meant there's been a licensing change to the Standard Edition.

The previous editions of Windows Server Standard Edition allowed for 1 instance of Windows Server to be installed as a Physical Operating System Environment (POSE) or as a Virtual Operating System Environment (VOSE). This meant that if you wanted to host a virtualised Windows Server 2003 R2 Standard Edition on say Virtual Server 2005 R2 running on Windows Server 2003 R2 Standard Edition, then you needed to acquire 2 licenses of Windows Server 2003 R2 Standard Edition - one for the physical instance and one for the virtual instance.

The new licensing change brings the Standard Edition in line with the Enterprise Edition. This means that Windows Server 2008 Standard Edition can be installed twice using the one license - once for the physical instance and once for the virtualised instance. The caveat is that the physical instance can only be used for the purposes of hosting the virtualised instance. All the workload for the Standard Edition license is to be performed in the virtualised instance, with the physical instance used to host and maintain the virtualised instance.

More information can be found in the Licensing Information section of the Hyper-V FAQ, Microsoft's Licensing Virtualisation changes and the Volume Licensing Product Use Rights.