Virtualization

Big bugs have lesser bugs

The Siphonaptera has various versions. The version I learned as a kid goes: Big bugs have little bugs, Upon their backs to bite 'em, And little bugs have lesser bugs, and so, ad infinitum. We make use of this fact a lot in computer security; a breach of the OS can impact the security of the application. We could even build a simple dependency list: The security of the application depends on The security of the operating system depends on The security of the hypervisor depends on The security of the virtualisation environment depends on The security of the automation tool.

Backup and restore

Have you tested your backups recently? I’m sure you’ve heard that phrase before. And then thought “Hmm, yeah, I should do that”. If you remember, you’ll stick a tape in the drive and fire up your software, and restore a dozen files to a temporary location. Success! You’ve proven your backups can be recovered. Or have you? What would you do if your server was destroyed? Do you require specialist software to recover that backup?

LXD and machine containers

A few months back I was invited to an RFG Exchange Rounds taping, on containers. There were a number of big name vendors there. I got invited as an end user with opinions :-) The published segment is on youtube under the RFG Exchange channel. Unknown to me, Mark Shuttleworth (Canonical, Ubuntu) was a “headline act” at this taping and I got to hear some of what he had to say, in particular around the Ubuntu “LXD” implementation of containers.

Virtualization All Change!

Just two weeks ago, I revisited my virtualization options with a view to making the system more reliable - primarily by using mirrored disks. In the end I stuck with a kludged up process for Citrix XenServer, but with a worry about how this would impact patching and upgrades. This week my XenCenter instance told me that 6.0.2 was out and I should upgrade. Now there are two ways to upgrade a XenServer; one is via the XenCenter console where it pushes the updates, the other is to boot off the CD and upgrade.

Virtualization Update

Two years ago I looked at some options for doing virtualisation at home. I decided on running Citrix XenServer. This has actually worked out quite well. So much so that I want to move some of my remaining physical hardware onto virtual. And here I run into a problem. XenServer doesn’t want to work nicely with mirrored disks. It’s expecting SAN or similar to provide the redundancy for disks. Now people have worked out options to convert a XenServer to a RAID disk, but I’m very very worried about how upgrades might break the OS partition.

Virtualization Options

Many of us are geeks who like to play with technology “because it is there”. We might want to try out a new OS, or a new piece of software. Maybe install a beta version of something, or be able to test a client-server setup. Historically that has meant having one (or more) test machines, configured as multi-boot. In 2002 I spent $600 on a Celeron 1200Mhz machine with 256Mb RAM and a 40Gb disk for precisely this purpose; it multi-booted into XP, NetBSD, Solaris 86, Fedora… at that point I ran out of primary boot partitions.

Thin Client Options

In my spare room I have what I grandiously like to call a library. (By library I mean approx 112ft of bookshelf space, on 3 of the 4 walls). What does any library need? A computer! Internet access, ability to print, access files etc. I have a random vision of the future of having my eBooks managed “somehow” (plug the eBook reader in, download the book(s) I want…). Nothing high powered; possibly playing youtube videos would be the hardest thing this computer would need to do.