Red Hat support

I've had Red Hat subscriptions for years. Basically, I've paid for access to their updates, ie. the ability to type "yum update" on a RHEL5 box, or the up2date equivalent in previous RHEL releases. US$350 / year seemed a bit steep for that, but the product is good so I paid it. We have some SLES infrastructure too, and the RHEL / RHN updates always works (SLES 10 updates break constantly), so we've stuck with them.

Anyway, yesterday for the first time I had the need to contact Red Hat support with a technical question to which I couldn't figure out the answer:

Our RHEL Xen host machine has filled up its root mount and I'm having trouble figuring out why:

[root@vodka ~]# df -H
Filesystem Size Used Avail Use% Mounted on
/dev/md0 5.1G 4.8G 33M 100% /
tmpfs 2.1G 0 2.1G 0% /dev/shm
[root@vodka ~]#

It hasn't run out of inodes:

[root@vodka ~]# df -i
Filesystem Inodes IUsed IFree IUse% Mounted on
/dev/md0 1280000 80028 1199972 7% /
tmpfs 497495 1 497494 1% /dev/shm
[root@vodka ~]#

And du reflects what I think the situation should be:

[root@vodka ~]# du / --max-depth=0 -h
2.1G /
[root@vodka ~]#

How is this possible? Being a Xen host, the machine has very little installed or running on it - it's just there to host 3 virtual machines. The virtual machines have their own software RAID partition each as their virtual HDD's.

The virtual machines appear to be running unaffected by the problem at the moment, but the host isn't getting updates from RHN (due to the full root mount, I'd be guessing).

Now, I'm on the "Basic" RHEL support contract, meaning 2 business day response time by web only (no telephone support), because I've never really valued the support option. Anyway, in around 24 hours I got a nice response advising me to look at the following two knowledge base articles:

http://kbase.redhat.com/faq/FAQ_35_5209.shtm
http://kbase.redhat.com/faq/FAQ_80_10743.shtm

After looking, they were bang on. Xen has this save directory that fills my disk, and somehow the file gets deleted, but Xen holds a file descriptor open to it, just like the first of those two knowledge base articles says. This is confirmed behaviour on the Xen-Users mailing list:

http://lists.xensource.com/archives/html/xen-users/2007-07/msg00510.html

Very annoying. But if you follow the instructions in that mailing list post (except the file on RHEL5 is in /etc/sysconfig/xendomains, not /etc/default/xendomains) and tell it not to save the file, then restart your xend and xendomains, the space gets freed up again.

Anyway, I'm really happy with Red Hat support. They provided me an answer in half their SLA time which helped me solve the problem. You might think you'll never use their support - for years I wondered if it was any good and worth paying for. It is, and it's worth having the RHEL subscription for.

VMware Server 1.0.6 on Ubuntu Hardy

I've just installed VMware Server (free as in price, but not open source), and on running up their GUI app (VMware Server Console) I get the following:

nathanr@raptor:~$ vmware
/usr/lib/vmware/bin/vmware: /usr/lib/vmware/lib/libgcc_s.so.1/libgcc_s.so.1: version `GCC_3.4' not found (required by /usr/lib/libcairo.so.2)
/usr/lib/vmware/bin/vmware: /usr/lib/vmware/lib/libgcc_s.so.1/libgcc_s.so.1: version `GCC_4.2.0' not found (required by /usr/lib/libstdc++.so.6)
/usr/lib/vmware/bin/vmware: /usr/lib/vmware/lib/libgcc_s.so.1/libgcc_s.so.1: version `GCC_3.4' not found (required by /usr/lib/libcairo.so.2)
/usr/lib/vmware/bin/vmware: /usr/lib/vmware/lib/libgcc_s.so.1/libgcc_s.so.1: version `GCC_4.2.0' not found (required by /usr/lib/libstdc++.so.6)
/usr/lib/vmware/bin/vmware: /usr/lib/vmware/lib/libgcc_s.so.1/libgcc_s.so.1: version `GCC_3.4' not found (required by /usr/lib/libcairo.so.2)
/usr/lib/vmware/bin/vmware: /usr/lib/vmware/lib/libgcc_s.so.1/libgcc_s.so.1: version `GCC_4.2.0' not found (required by /usr/lib/libstdc++.so.6)

As it turns out, VMware override the local libraries that are installed on your system. If you cancel the override for libgcc then the problem goes away and the VMware Server console works. To do so, edit /usr/lib/vmware/lib/wrapper-gtk24.sh and find the line:

vm_append_lib 'libgcc_s.so.1'

And then comment it out as such:

#vm_append_lib 'libgcc_s.so.1'

Now VMware Server Console will work.

"Free" Sun Solaris

I've spent a few days investigating Sun's software stack. And I've found a few cool things:

• Large parts of their "Java System" software stack have been open sourced. Two which really interested me were their Java System Application Server (Glassfish) and Java System Access Manager (OpenSSO).



• The commercial Solaris is now freely downloadable, and the license says that you can run it in a commercial environment free of charge, and pay for it only when you want support.

Now, this opens a can of worms. The word "support" for mine means "technical support", as in I can ring the vendor, email the vendor, and they have a service level agreement in place such that they'll answer my question within a guaranteed period of time.

Great, I thought - I don't want to ring Sun for technical support, I just want some software. Apparently not, according to their FAQ:

Are patches available for free? And, if I download software are the patches free?

In the past, Sun charged for software releases and gave patches away for free. Now, Sun gives the software releases away and charges for most patches. This new model is similar to the model used by some Linux vendors. [...] However, Security and device driver patches are free.

Ok, so you need to pay for bug fixes, but security updates are free. Do you know how hard that was to find on their website though? It's easy to find the "download Solaris for free" links all over the website, but it took me two hours to find the "pay for the patches" clause hidden away in a FAQ. It's not even in the license agreement.

Oh well, no drama. After all, at least you're getting security updates. Well, yes - the hard way. According to that FAQ:

To find a free patch, locate the patch ID in the patch list that does not show a key icon. Those patches that cost show the key icon.

1. On the SunSolve site, find the “Download Product Specific Patches” section at the bottom of the page.


2. Find the “Software, Solaris” section and Select OS drop-down menu.


3. From the drop-down menu, obtain the correct patch list by selecting the release and platform type.

In other words, it's such a pain that nobody will bother. I wonder why that would be. Don't worry - Sun answer that one too:

You can purchase a support contract to obtain patches for a fee. Or, if you upgrade to the next Solaris 10 release, such as the Solaris 10 4/08 release, this release contains all the available bug fixes.

... and then you can use their automated patch management tools.

So there you have it - Solaris and all the enterprise software stack can be downloaded and installed on your production servers for free. However, at least with the Solaris OS, you'll need to pay if you care about the security of your servers. So nothing has really changed then, I guess. I can't for the life of me find any information on free patches any of the rest of the stack, so who knows what the story is with that.

So I thought I'd download the open source web server (Glassfish), and opened the update manager. In there are tick boxes to download the commercial Java System Access Manager, not the open sourced OpenSSO. WTF?

Sun have done some great things in open sourcing some truly great products. Glassfish is genuinely good, and I really hope Sun doesn't ruin it by silly vagueness in their support arrangements. Otherwise we'll all just stick to Tomcat on Linux and bypass them all together.

Starting out rallying

Recently my brother purchased a new VW Golf GTi, and with the money from the sale of his 1997 VW Polo we're considering building a rally car and starting out competing in local rallies.

I've done a bit of research, and it looks like the Excel Rally Series is the entry to the sport in Australia. According to that site it costs $8-10k to build a car, and from what I gather the basics you need are:

• A third generation Hyundai Excel (preferably the later ones, which were DOHC and more powerful than the earlier SOHC models).


• Roll cage


• Some sort of suspension changes


• Rally tyres


• A few spare rims for when you get a flat tyre


• Race brake pads


• Trailer for towing car to and from events


• Fire extinguisher (not sure how serious the fire system needs to be)


• Bonnet pins and tow hooks


• Mud flaps


• Clubman Rally license from CAMS

Anyway, as I figure more out I'll post it. If I actually get around to building this car then I'll post up a "cheat sheet" of what's needed, costs, and who I got mine from, so that the next person who is interested in getting started in rallying doesn't need to find out all this stuff from first principles.

Java 6 and java.awt.Desktop

In a current application we're writing, we've got a use case where you can upload a file, and later download it by pressing the "View" button, which will open the file in correct application for the user.

We're using Java, and I thought this would be a nasty task full of pain and suffering, but to my suprise Java 6 includes a class which does exactly this: java.awt.Desktop. Here's some sample code which will open a PDF file on my disk.

import java.awt.*;
import java.io.*;

public class Test {
    public static void main(String[] args) throws Exception {
         Desktop.getDesktop().open(new File("/home/nathanr/Desktop/file.pdf"));
    }
}

Cool, huh? Now I'm sure you Windows / .NET people are saying "that's not hard - we've been able to do that for $x years". Sure, but the above will work on Linux and Mac too.

Fix: F-Spot opening Gimp for RAW files on Ubuntu Hardy

In the previous post, I described how to fix Ubuntu (Hardy - 8.0.4) to get photo importing working with the F-Spot photo management application it ships with, so now to get F-Spot to use Gimp to edit the photos you've imported.

Now, it would seem that Ubuntu ships in a working way if you've imported JPEG files off your camera. However, if you've got a decent camera (ie. DSLR) you've no doubt switched your camera to RAW mode, which for me is Canon CR2. You'll find that:

1. You can view the RAW files in Nautilus (the Gnome file manager)
2. You can view the RAW files in F-Spot
3. When you right click in Nautilus, you'll notice that Gimp is there and will open the file
4. But you'll notice that when you right click on the photo in F-Spot, the "Open With" menu is blank.

The rest of this post deals with how to get Gimp to appear in the "Open With" menu for F-Spot.

Ok, so there are two things missing.

1. The MIME type for the raw file type is missing
2. The Gimp application description file is missing the mime type that says "I can open raw files"

But firstly, make sure you have ufraw, gimp and f-spot installed, including the gimp-ufraw package.

Now, to fix problem #1, add a file in the directory "~/.local/share/mime/packages" called "canonraw-mimetypes.xml", with the contents:

<?xml version="1.0"?>
<mime-info xmlns='http://www.freedesktop.org/standards/shared-mime-info'>
<mime-type type="image/x-canon-cr2">
<comment>Canon RAW</comment>
<glob pattern="*.cr2"/>
</mime-type>
</mime-info>

Now, to fix problem #2, you need to edit the gimp.desktop file. As root, edit the file "/usr/share/applications/gimp.desktop", and on the line that begins with "MimeType=" you need to add "image/x-canon-cr2;" to the end of it.

Now, update the Gnome MIME database:

nathanr@falcon:~$ update-mime-database ~/.local/share/mime/

After logging out and logging in the "Open With" menu should include Gimp for *.cr2 files.

Note to Mac users: you can ignore this post. It's another case of "it just works on the Mac".

Fix: Importing photos on Ubuntu Hardy

A few weeks ago importing from my Canon EOS 350D to my Ubuntu machines was working, but at some point an update has broken it. I spent a bit of time this morning finding out why. (For those of you who have never tried using an Apple Mac, this stuff never happens on a Mac - things just work.) Anyway...

There are two separate stuff-ups at the moment. The first is that the pop-up that asks you whether you'd like to import your photos doesn't come up when you plug-in your camera. Don't know why this default was changed, but you can switch it back on as described in this forum post.

Ok, so now if you plug in your camera, F-Spot will pop up and say:

Received error "Could not claim the USB device" while connecting to camera

The answer is based on a forum post and a blog entry I found on the web. However, they're not 100% accurate, because the file "/etc/udev/rules.d/45-libgphoto2.rules" no longer exists. So I added the file back with the one line:

SYSFS{idVendor}=="04a9", SYSFS{idProduct}=="30ee", MODE="0660", GROUP="plugdev"

The "04a9" is the ID for Canon, and the "30ee" is the ID for the EOS 350D. You can find your IDs by the "lsusb" command:

nathanr@raptor:~$ lsusb
Bus 008 Device 004: ID 04a9:30ee Canon, Inc. EOS 350D
[...]

Look for the entry for your camera, and copy the bit before the ":" as your vendor ID, and the bit after the ":" as your product ID.

After that, and a restart of udev:

nathanr@raptor:~$ sudo /etc/init.d/udev restart

Then things started working; and once again we relearn the age old truth - Linux is only free if your time has no value. How I miss Mac OS X and Apple's iPhoto.