Dennis Krul

It’s been a bit quiet on my blog for a while. Not that I don’t have anything to talk about, I’ve actually been quite busy These are exciting times! Four weeks ago, our son was born! I proudly present: Thijmen!

He’s a very healthy boy. He sleeps very well (also during the nights fortunately) and he’s growing really fast! My girlfriend is doing really well too and she has almost completely recovered. I’m glad everything went ok.

Just watch this one, it’s hilarious! Hah

Kemari is a virtual machine synchronization mechanism for Xen. It allows you to run a hot standby copy of a virtual machine on a different host. If the active host becomes unavailable for some reason, the standby host takes over without downtime. (Note that this is different from live migration, where both nodes need to be up and running.) This allows for higher availability of your servers. Of course VMware had this feature for some time, but I’m glad someone is working on an open source alternative.

Unfortunately most of the Linux distributions are focusing on KVM instead. For RedHat this makes sense, because they acquired Qumranet (who developed KVM). But Debian and Ubuntu also pretty much gave up on Xen. The only mainstream Linux distribution still actively working on Xen support is SuSE. Actually, the only UNIX based platform that really has good Xen integration is not even Linux based, it’s OpenSolaris, go figure.

I agree that in the long run a Linux kernel based approach to virtualization makes sense, but I also believe today Xen has an edge over KVM and will keep that edge, probably for years to come. Why not bet on both horses and let end users decide which virtualization solution to use?

Today I’ve been playing with virt-manager/libvirt (a Redhat emerging technologies project) on the new upcoming Ubuntu release Intrepid Ibex (8.10) and.. well..  it just works! I’m using it with KVM, for which you need hardware virtualization support.

It’s quite easy to create a new virtual machine, just clicky-clicky in the GUI, select an ISO to boot from and you’re ready to go. Even networking is automatically configured for you (using NAT by default). I’m impressed! Thank you, Redhat and Ubuntu developers, wherever you are!

Matt Colyer and friends have been busy reverse engineering the USB protocol used by Apple to sync iPhone and iPod touch devices and is now working on iFuse, an impressive project that will provide native USB access to those devices in Linux without the need for jailbreaking! As the name suggests, it is implemented as a FUSE filesystem.

By the way, you still need an app using libgpod to actually update the music library database on the iPod. iFuse only handles the mounting of the filesystem. I’m not sure if this works with Rhythmbox (since it uses libgpod for iPod support), but I guess I’ll just have to try. At least it works with gtkpod for the time being, which is better than the slow and inconvenient alternatives: jailbreaking and syncing over WiFi or running iTunes in a virtual machine (I use vmware player for this, because it is the only solution to properly virtualize USB 2.0).

This week VMware released updated versions of their Workstation and Player products. This fixes a long standing issue with USB support for the iPod touch and iPhone. I’m now finally able to sync my iPod touch from iTunes in a virtual machine! Just don’t try to update your firmware from a virtual machine.. It fails and renders the device unusable until you flash it from a native (non-virtualized) iTunes :S

Not being able to sync my iPod touch was one of the major regressions I had since I dumped Windows. It still is not the best possible solution, because I still need Windows in a virtual machine for this to work. Unfortunately there hasn’t been much progress with regard to native Linux support for these things without jailbreaking them..
If I’m going to buy a new portable music player some day it sure as hell isn’t going to be an Apple product, unless they open up and allow other people to interface with them. If you are a Linux user: Don’t buy one of these things. I know they’re sexy and all, but really .. don’t!

I installed a reCaptcha plugin for Wordpress, which allows people to directly comment on my posts without having to register for an account first. Should be effective against spammers, who (despite the fact that they had to register for an account) were spamming my moderation queue.
If you also happen to run Wordpress I highly recommend it! Simply sign up for an API key, drop the files in your plugin directory and enable the plugin from the admin interface. As an added bonus you help to digitize books (Did I mention it is free?)

I just discovered that OpenLDAP now supports multimaster replication! This means there finally is a serious enterprise-ready(?) and open alternative for the Netscape directory server family (on which both Fedora DS and Sun JES are based iirc). Without multimaster replication it is impossible to create a real redundant directory setup, which is what you want when your whole data center depends on LDAP for authentication/authorization or other types of lookup maps. (Well, you could always just replicate the directory, but you would not be able to change anything in it while the master server was down.)
From the OpenLDAP roadmap:

OpenLDAP 2.4 (released October 2007)

Functional enhancements and improved scalability:

• Updated slapd dispatcher
• MirrorMode and MultiMaster replication
• Proxy Sync replication
• Expanded monitoring
• Multiple new Overlays
• Expanded documentation
• New socket backend (experimental)
• LDAPv3 extensions:
  • LDAP Chaining Operation support
  • LDAP Don’t Use Copy Control support
  • LDAP Dynamic Directory Services (RFC2589)
  • LDAP Transaction support (work in progress)