Since upgrading to Ubuntu 9.10 I’ve noticed poor performance of VirtualBox guests with Intel VT-X hardware virtualisation enabled. This has been noted in a few places, but I didn’t enable VT-x until recently so I can’t be sure that the problem began with Karmic. I can be sure that it is happening to me now.
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Tags: amd64, karmic, ubuntu, virtualbox
Friday I upgraded from Kubuntu 9.04 “Jaunty Jackalope” to Kubuntu 9.10 “Karmic Koala”. Here are my notes on the upgrade.
You really shouldn’t allow SSH logins via password. This is doubly true for root. On most of my hosts we allow SSH for normal users with a password, but restrict root to SSH keys only. And we always protect against brute force attacks with fail2ban.
If you aren’t already using SSH keys and SSH agent, you should. SSH agent forwarding allows for secure sideways authentication. For example:
Cleaning up after the KDE 4 upgrade continues. Today I tried to port kregexpeditor from hardy, but pbuilder stopped with a library conflict:
kdelibs5-dev: Conflicts: kdelibs4-dev but 4:3.5.10.dfsg.1-1ubuntu8 is to be installed
I’m sure I could have resolved this, but I decided to test the hardy package before spending any more effort. The package installed without complaint, and the binary runs. I’ve added the amd64 and i386 packages from hardy-backports to the repo for jaunty.
Until last week I still ran Kubuntu 8.04 (Ubuntu with KDE) on my personal desktop. We also use this on all our corporate desktops, and my wife’s PC at home. I wanted to wait for KDE 4 to mature a bit more before upgrading, so intrepid wasn’t an option.
I waited 4 months after the release of jaunty, so the problems should be either documented or resolved, and the release notes didn’t mention anything that seemed too serious. So I decided to give it a test.
I love SSHFS. I manage a lot of machines, and I very often want to do something like this:
diff root@server1:/etc/randomrcfile root@server2:/etc/randomrcfile
There are ways to do this with Kompare (a KDE diff app) and the fish:// Kioslave, but not on the command line. SSHFS makes it easy:
mkdir /tmp/server1 /tmp/server2
sshfs root@server1:/ /tmp/server1/
sshfs root@server2:/ /tmp/server2/
diff /tmp/server1/etc/randomrcfile /tmp/server2/etc/randomrcfile
I do this so often that I’ve written my own script to handle this for me, smount. Copy it somewhere in your path, and optionally make a copy or symlink called “sumount”. Now you can rapidly mount and unmount multiple hosts.
As I mentioned in my last post, I now have a Home Theater PC (HTPC). Want to look under the hood?
I recently bought a Shuttle X27D to use as a Home Theater PC (HTPC). The reviews of this hardware run from disappointing to average, but I’m reasonably happy with it. It’s quiet (just one small fan for the GPU, and none for CPU, case, or power supply), uses little power (I measured it at 32 W in full operation), and the analog audio jack on the motherboard has no discernable noise in the audio stream (unlike my Dell Vostro 1500 laptop).
Unfortunately, the Intel 945G graphics processor can’t reliably handle 720p @24 frames video. I tested with a downloaded copy of Sita Sings the Blues, and it dropped frames as the animated fireworks exploded during the title sequence. It was fine with most of the rest of the film. Still, it means I’m likely to stick to upscaled 480p video. Which is far better for my bandwidth usage.
Naturally, I ran into some problems setting it up.
I recently posted about backporting packages with pbuilder. Someone asked about forward porting PHP4, which is a huge task. PHP4 is out of date, and the entire set of PHP4 libraries has a lot of build dependencies, including some packages you must build yourself. I’m not going to take you through the process of backporting PHP4. If you really need it, you can install php4-cgi and php4-* from Ubuntu dapper directly on hardy. But I will show you how to enable a local repository in pbuilder. This will allow you to build a package with pbuilder, and then use that package to satisfy any build-dependencies that other packages need.
Finally, finally, FINALLY! The Sun Java plugin now works on Firefox amd64 in native 64-bit. It has already been included in Ubuntu 9.04 Jaunty, but the packages work just fine on Hardy as well, and probably on Intrepid.
Just download and install the Jaunty versions of sun-java6-bin, sun-java6-jre, sun-java6-fonts, and sun-java6-plugin. Install them, and remove the old icedtea plugin if you have it:
sudo dpkg -i sun-java6-bin_6-13-1_amd64.deb sun-java6-fonts_6-13-1_all.deb sun-java6-jre_6-13-1_all.deb sun-java6-plugin_6-13-1_amd64.deb
sudo apt-get remove --purge icedtea-gcjwebplugin
Then restart Firefox and Sun java will load natively 64-bit. Check it:
tyler@baal:~$ java -version
java version "1.6.0_13" Java(TM) SE Runtime Environment (build 1.6.0_13-b03) Java HotSpot(TM) 64-Bit Server VM (build 11.3-b02, mixed mode)
I’ve included them in the repository.
Update 2009-07-16: A more recent version is now available in the hardy-updates repository. I have removed the above copy from my repo. Intrepid users should upgrade to jaunty anyway, but can still download packages directly.
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