Virtualising Legacy CentOS 4.x Servers

Home » CentOS » Virtualising Legacy CentOS 4.x Servers
CentOS 5 Comments

Dear all,

I look after a number of CentOS 4.x servers running legacy applications that depend on ancient versions of various things (such as MySQL 3.x) and which can’t be upgraded without non-trivial development effort.

I’ve been considering virtualising them and as a test have been trialling with a company that uses Parallels Cloud Server 6.

However, I’ve run into a roadblock in that the Parallels Tools installer in PCS6 require a version of glibc higher than that which is available in CentOS 4.x (v2.5 required versus v2.3.4 installed).

Without the guest OS tools installed it’s impossible to migrate a VM
from node to node or back it up without shutting the VM down first, which is less than useful.

So I have two questions:

1) Does anyone know if there is a version of the PCS6 Tools built against glibc 2.3.4 available anywhere?

2) Is there an alternative virtualisation environment I should be looking at which fully supports CentOS 4.x as a guest OS? And if so, does anyone have recommendations for a hosting supplier that offers that environment (ideally UK based).

Many thanks Simon

5 thoughts on - Virtualising Legacy CentOS 4.x Servers

  • If you are running physical machines now, you don’t have that ability anyway…

    Does it have to be hosted? You could run under KVM/Virtualbox/Vmware, etc. on your own hardware. If you have any internet exposure you can’t expect to survive long without update support, though.

  • At 12:58 -0500 14/5/14, Les Mikesell wrote:

    True, but that’s a reason to try and migrate to a better environment which would allow it.

    Yes, it has to be hosted. Aiming to get away from having to own physical hardware with all that entails support-wise.

    S.

  • I’ve had to do the same for one system as well. In my case we’re slowly trying to kill (migrate) off that machine, but the physical-to-virtual transition bought us some time.
    ( It was a hardware nightmare and power reduction win. )

    If you can build, configure, and maintain a KVM set up then it would be worth your while.

    For the VM, it not too hard to set up the partitions, format the file system (be careful of ext specific flags that may need adjusted from the default!), rsync the files, install a bootloader, and re-roll the initrd with virtio support (if necessary).

    I know some people use Clonezilla to migrate VMs. I’m sure we’d find other people have alternative methods if those people speak up!

    Good luck.

  • CentOS 4 should virtualize just fine under Xen. You will need to install the kernel-xenU package if you want to run it as a PV domain
    (recommended). At the time I think that Xen was RedHat’s virt of choice.

    While I haven’t tested C4 explicitly of late, it should run just fine under Xen4CentOS in the dom0. You can backup without shutting down the domain from the dom0 if you want if you use LVM and just take a snapshot, then just mount the snapshot and backup from there.

    Peter