Nathan Robertson's weblog

Joel’s “User Interface Design for Programmers”

2009-11-04T19:27:00.001+11:00

A while ago, after reading Joel on Software, and making all of my development team at the time read it (all recruits since have also read it), I decided that Joel Spolsky was a great author and I should buy all his books. And I did – I read “More Joel on Software” and was disappointed; Smart and Gets Things Done shares a lot of content with the original Joel on Software book; and my latest read was User Interface Design for Programmers. I really had my hopes up for this book – there are very few books around about UI design, and I really wanted this to be a good book that I could hand on to programmers who work for me and say “this book has lots of simple and useful advice – stick to what Joel says”. I really wanted this to be “the book” on UI Design.

It’s not. It has lots of interesting anecdotes, useful tips, and some good points; but it doesn’t feel like the “A to Z of UI Design” that I was hoping for. I guess this might be my expectations – Joel on Software was a great book which is the simplified “A to Z of software project management”, so my expectation for his UI book to be equally authoritative wasn’t met.

It’s not a bad book, but like I said in my review on More Joel on Software – it’s not the killer book that the original Joel on Software was. And if you haven’t read the original Joel On Software, then buy it and read it. It’s brilliant.

More Joel on Software

2009-08-23T20:08:00.001+10:00

Think of a great sequel movie. Terminator 2 comes to mind. The original wasn't great, was it? Now think of a great movie with a really disappointing sequel. The Matrix is the one that most people remember in that category - the original was so good that the sequel could only be a let down.

Joel on Software is the best single book on software development I've read. Every developer I've hired has read it, and every one of them has agreed that it's a great book. It is a book of useful tips and simple strategies for building software that works. I could go on for pages describing how brilliant it is; honestly, just go and buy it.

Unfortunately, there's a sequel - More Joel on Software. As soon as I saw it I thought "wow - another 300 pages of invaluable advice that I'll be able to use". Probably in the same way you thought "wow - another matrix movie that will blow me away". Anyway, I've just finished reading it - there are several chapters which were useful to read, several which were padding the book out to 300 pages, and lots which I read and don't remember.

So, at the end of the book I'm filled with disappointment. The problem isn't that the second book is rubbish; it's not. It's that the first one was so brilliant, and the second one was a bit ho-hum. I was prepared to be blown away all over again, but instead I just learnt bits and pieces, just like many other books.

By the way, I never did go to see "The Matrix Reloaded", nor did I bother with the third one, mainly because friends told me it was nowhere near as good as the first. So, as your friend I highly recommend you buy the first Joel on Software book. It's brilliant.

Apache Maven and Ivy

2009-08-15T14:20:00.003+10:00

I went to a Canberra Java Users Group meeting on Wednesday night, where Glen Smith was giving a presentation on Apache Maven. I'd previously looked at Maven, and found it complex, confusing, poorly documented, and not really offering anything I wanted that Apache Ant didn't already do.

Anyway, apparently the documentation part of my complaint has been solved - Glen recommended the O'Reilly book on Maven - it's a free PDF download, and written by some core Maven people, due to the common complaint about the lack of decent documentation.

It did some cool things, but most of them are things which my Ant scripts do for us. The only thing it really did that I thought would be useful was automatic downloading of updated third party jars (think "yum update" every time you do an "ant build"). There's a plugin for Ant to do this (Apache Ivy - http://ant.apache.org/ivy/). The concept is pretty cool - stops me from needing to go through our third party libs every now and then and updating them by hand, and drops the size of our subversion repository as well.

So I looked into this further. Ivy uses the Maven master repository as its default upstream repository for solving third party library dependencies. So I looked at the versions of some of the libraries we use:

SWT - 3.0.1, last updated January 2007. We're using 3.5.0. Not much good.

Apache FOP - 0.93, last updated May 2007. We're using 0.95. Not much good.

Apache Struts - 1.2.9, last updated Jaunary 2007. Latest 1.x is 1.3.10, we're using 2.1.6. There is nothing in that repository for Struts 2.x at all! Not much good.

And so it goes on. It looks like a great framework for updating to packages that are at least two years out of date. (To be 100% honest, there are packages that are up to date; but looking down the list, the majority look to be years out of date).

Oh, the one thing Glen did say Maven was really good with was sharing code amongst multiple teams. You have your own Maven repository, and publish versions there, and other projects pull them down automatically when they build. That seems cool, but irrelevant if you aren't a large organisation with multiple development teams.

So it was an interesting presentation, and convinced me that I was right to ignore it for our purposes.

Red Hat subscriptions on non-RHEL hypervisors

2009-06-10T09:49:00.002+10:00

Over the past six months, we've started to use Citrix XenServer for virtualization, migrating away from VMware Server and Red Hat's bundled Xen that is in Red Hat Enterprise Linux (RHEL).

On our testing, XenServer is the best virtualization package currently available. The management tool (XenCenter) is pretty much as good as VMware's VirtualCenter, and anyone from an ESX server background will feel right at home. The big difference is that XenServer runs on pretty much any hardware (because underneath it just uses the Linux dom0 instance for drivers). By comparison, the VMware ESX server Hardware Compatibility List is pretty bare, and will only run on specific machines from the big hardware vendors.

Anyway, this post is about RHEL subscriptions and licensing. I submitted the following in a support case to Red Hat:

Case Title : Virtual instance licensing on non RHEL hypervisors

Hi,

We've got a Citrix XenServer deployment to which we are looking to migrate some RHEL servers to. How do RHEL subscriptions work with non Red Hat shipped hypervisors (ie. VMware, Citrix, Hyper-V, etc.)?

1. Can I purchase Advanced Server subscriptions per-node?
2. Can I purchase Basic subscriptions for nodes with 4 or less RHEL VMs?
3. Or is it "per VM" if we're not running a Red Hat badged hypervisor?

I can't find anything on redhat.com about this. I assume it's #1 and #2, given this is what Novell / SuSE do (http://www.novell.com/products/server/virtualization.html). "one subscription to SUSE Linux Enterprise Server covers all virtual images on the same physical server".

Assuming this is the case, how do I go about registering the VMs with RHN?

In response, I got the following

Welcome to Red Hat support .

Since you are using Citrix XenServer deployment each of the virtual machine will be considered as a separate physical machine and you will have to purchase subscriptions for each virtual machine .

If you are using rhel vitalization you can have a single subscription and register unlimited guests .

http://www.redhat.com/rhel/server/advanced/

or

Red Hat Enterprise Linux server subscriptions provide support for up to four virtualized guest environments.

For more details you can check this link

http://www.redhat.com/rhel/virtualization/

But since this is a third party vitalization you will need subscription for each virtual machine .

So, if you're using a competing virtualization technology, you pay per VM. The difference in costs is huge - if you're running several virtual machines per physical machine, you'll pay several times as much to Red Hat. Time to start looking at Novell's SuSE Linux Enterprise Server or Ubuntu again.

Zimbra support

2009-05-09T11:34:00.006+10:00

A while ago I posted a positive review of Red Hat's support - first time I'd ever used it. Well here's another positive support story on an open source company - this time Zimbra. They make a quite good groupware package, roughly equivalent to MS Exchange - their AJAX webmail client is apparently better than the MS equivalent (never used the MS one), and the paid for version of the product supports MS Outlook and Windows Mobile / iPhone devices.

A few weeks ago, we had a full day outage where our mail server was thrashing its disks hard. After working away at it for a while, we somehow managed to get the server under control. Not having any idea what happened or what caused it, we decided to use one of our two Zimbra support cases for the annual subscription.

What followed was excellent - we lodged a case with the Zimbra online customer portal last thing before leaving work - a support engineer responded the next day asking for some specific data. They looked at the data, and asked for some more data. This happened several times, but in every case their turn around time was quicker than we expected (typically under 48 hours). Twice, the support engineer actually consulted with the developers of the product, and reported back to us some very informative feedback on the outage. The second of these was actually quite detailed, and the developer would have taken some time to diagnose, consider then write a good response.

So there you have it - another good service report. Zimbra aren't cheap - for us it's about US$1900 (AUD$2500 currently) per year (26-50 user license). MS Exchange is about AUD$6000 outright (ie. 10 years support, patches, but no upgrades). But I couldn't dream of that type of support from Microsoft, so I think we'll renew our Zimbra contract when it comes up at the end of the year.

Windows Vista crcdisk.sys crash

2009-02-22T11:13:00.002+11:00

So, I decided that the laptop I've had for the last year or so with Linux installed on it needed to be dual boot with Windows. The laptop in question is a Dell XPS M1330, 4GB RAM, 200GB 7200RPM HDD, Intel graphics. These are basically the specifications that Dell in certain areas of the world sell supported with Ubuntu Linux. However, in Australia you must buy it with Windows, you can't order it without. I'm sure plenty of other people have whinged about this, so I won't - I'll just say that given the choice, I would have ordered it without Windows.

Anyway, I've found that about once every two months I was booting my copy of Windows I was forced to purchase with the laptop in Sun xVM VirtualBox. Unfortunately, the version of Windows that was enforced on me was Vista, so that's quite slow in a VM. So, for the first time in its life, I installed Windows on the laptop.

After installing Windows, installing all the drivers, several reboots, then running Windows Update, the machine gets itself into a reboot loop. When booting in safe mode, it gets to "crcdisk.sys", then flashes a blue screen of death, and automatically reboots itself, and does this in an endless loop.

Now for the solution - rip out 2GB RAM. Apparently one of the updates Microsoft shipped stuffs something up such that if you have more than 2GB RAM, Vista won't boot. Wow, well done guys. Anyway, here's how to take memory out of a Dell XPS laptop. Now my laptop boots again - after all the updates have applied, I'll put the memory back in and hope it works.

I never thought I'd see the day when a mainstream hardware vendor ships a laptop that works better with Linux than Windows. But it just has - the vendor is Dell, and the laptop is the XPS M1330.

GpxUpdate source released

2008-12-30T23:28:00.003+11:00

A few months ago I wrote a quick bit of hobby code which I called GpxUpdate. Today I got around to putting the source code up on SourceForge. Taken from the "about" section on the website:

GpxUpdate is a Geocache manager that allows you to update co-ordinates for puzzle caches, then export a modified GPX file. From there you may choose to convert to Google Earth format, copy to a GPS, copy to a PDA, etc.

The important thing is that it stores changes to files, rather than the file itself, meaning you can continually update the GPX file from geocaching.com, then apply the changes for the caches you've solved.

It's freely available (both in source code and as an end user program), and can theoretically run on any platform that supports Java and has a port of SWT/JFace. It has been tested on Linux and Mac OS X, and should work on Windows.

I've found this application really useful. I have a weekly scheduled pocket query on GeoCaching.com which sends me a list of the 500 nearest caches to my house that I haven't found. I then load the file into GpxUpdate, then press the Save button to export a modified GPX file, which I then use gpsbabel to export a Google Earth KML file, and also export to my Garmin GPS. I also copy the modified GPX file to my PDA for paperless caching.

During the week, as I figure out answers to the puzzle or multi caches, I update the co-ordinates in GpxUpdate. When I find a cache, I untick the box next to it in GpxUpdate (only ticked caches are exported). This means that when I sync my GPS, KML file and PDA, I get a list of only those caches I haven't found (regardless of how old my original query file is), and I get the updated co-ordinates on my GPS, meaning when I finally go to hunt the caches down, I can treat them like regular traditional caches.

Red Hat support

2008-09-23T09:25:00.002+10:00

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

2008-07-16T16:53:00.002+10:00

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

2008-07-02T20:44:00.006+10:00

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

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

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

2008-05-19T20:24:00.003+10:00

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

2008-04-29T14:44:00.004+10:00

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

2008-04-06T16:10:00.004+10:00

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:

You can view the RAW files in Nautilus (the Gnome file manager)
You can view the RAW files in F-Spot
When you right click in Nautilus, you'll notice that Gimp is there and will open the file
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.

The MIME type for the raw file type is missing
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

2008-04-06T10:59:00.002+10:00

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.

Dell XPS M1330

2008-03-24T13:04:00.002+11:00

After a couple of months not being able to use my Apple laptop for work, I decided to buy another one. And as usual, I looked hard at PC laptops at the same time. Unlike the last three times, this time I did buy a PC, however. A Dell XPS M1330, as recommended on the Ubuntu website. In Australia, we aren't able to buy this laptop pre-installed with Linux, so I had to get it with Windows Vista.

I took the onboard Intel graphics (not the nVidia), as it's better supported, and the 7200RPM hard disk, with the Intel wireless chipset. All in all, this laptop running Linux has stunned me with how well it works. I haven't bothered trying the onboard camera, but I haven't had to stuff around with anything really. Even when I plug it into the 22" LCD screen at work, it does desktop extension wonderfully.

And that's the thing. They're now 90% as good as a Mac. And in 12 months time when I want a new one, I can hand it on to somebody else at work and get another, because it has a Windows license, and in the meantime I can legally have Windows Vista running in a VMware Server instance for the odd thing I want to do in Windows.

But I haven't defected from the Apple clan - I'm just in exile. I still have my old MacBook as well.

Fix: Samba PAM validation errors

2008-02-22T15:54:00.002+11:00

Here's one I hope Google will index so that the next person who comes across this problem can solve it quickly.

I have a Windows 2003 R2 Active Directory domain controller, and have several Linux Samba servers which serve files for Windows users. I had one particular user who would get this error:

[2008/02/22 15:38:54, 0] auth/pampass.c:smb_pam_accountcheck(781)
smb_pam_accountcheck: PAM: Account Validation Failed - Rejecting User DOMAIN\username!

when accessing a Samba server, but is able to access things on the Windows 2k3 server. As it turns out, I hadn't configured PAM properly. In /etc/pam.d/samba I changed it to be:

@include common-auth
#@include common-account
account required pam_winbind.so
@include common-session

I restarted Samba and things work now.

PositiveSSL and Apache Tomcat 6

2008-02-11T14:27:00.000+11:00

I had to renew an SSL certificate for our production web server today. This proved to be more painful than I thought it'd be, mainly due to out of date instructions provided by the certificate vendor. FWIW, we use Comodo PositiveSSL, and it's cheap so I'd recommend it.
Anyway, here's how to get it to work with tomcat:
$ keytool -genkey -alias tomcat -keyalg RSA -keystore keystore.jks

The first question it will ask is "What is your first and last name?". Don't type your name. This should be the name of the server (eg. "www.yourcompany.com"). The rest of the questions you can answer as usual.

$ keytool -certreq -keyalg RSA -alias tomcat -file certreq.csr -keystore keystore.jks

Now, you fill out the PositiveSSL webform, putting your credit card and other details in. It's ask you to paste in the Certificate Signing Request as well - just copy and paste the contents of the certreq.csr file into that field. After a few minutes, you'll receive a couple of emails, the last of which will have a zip file attached, which has four crt files in it. Now you need to import these in a particular order.

$ keytool -import -alias root -keystore keystore.jks -trustcacerts -file AddTrustExternalCARoot.crt

This step may warn you saying "Certificate already exists in system-wide CA keystore under alias". Tell it that you do want to add the certificate despite whatever it's warning you about.

Then add the rest of the certificates that were in the zip file in order:
$ keytool -import -trustcacerts -alias addtrust -keystore keystore.jks -file UTNAddTrustServerCA.crt
$ keytool -import -trustcacerts -alias positive -keystore keystore.jks -file PositiveSSLCA.crt
$ keytool -import -alias tomcat -keystore keystore.jks -file www_yourcompany_com.crt

Windows XP installer crashes

2008-01-27T17:48:00.000+11:00

Very rarely, I have the need to take a machine which had a Linux distribution installed on it, and need to reinstall it with Windows. Typically, it's a work laptop for which I have temporarily borrowed, and need to return it to the state I got it in.

Recently, I've had two machines which the installer crashes whilst booting the Windows XP install CD, still on the black screen. Any Linux installer will boot fine, however. It took me a fair while to rule it down to Linux having written to the MBR of the disk, and Windows installer getting confused. I didn't guess this initially, because I thought Windows would just overwrite it. But apparently not.

So, if you've got an ex-Linux boot disk, and you want a Windows XP (Home or Professional) CD to boot with it, then boot a Linux install CD in "rescue mode" (I used the CentOS 5 DVD, and typed "linux rescue" at the first prompt). Then, once it's booted and you've got a shell type:

dd if=/dev/zero of=/dev/hda bs=512 count=1

This will make your previous Linux install fail to boot; but that's fine, I wanted the machine to boot Windows only anyway.

Mac OS X v10.5 and Java 6 (Part 2)

2008-01-16T00:57:00.000+11:00

I was browsing the Apple Developer site today in the vain hope that they might have addressed the problem of the lack of a Java 6 SDK for Mac OS X. I must admit, after over three years of using a Mac for my Java development at work, I had started using a Linux PC again.

Anyway, I was shocked to see that Apple had indeed shipped a new beta of JDK 6, now at Developer Preview 8. I almost downloaded it too, but I read the fine print. Only works on Mac OS X 10.5 (Leopard), and only works on 64 bit Intel Macs.

Now, I'm running Leopard, but I've got a first generation MacBook with the Core Duo (not the Core 2 Duo, which was 64 bit). This machine is less than two years old, and Apple are going to force me to upgrade to return me to the functionality that I had before their (paid) upgrade to Leopard.

So I guess I'll be forced to keep using a Linux PC for Java development work a little while longer.

Updating with SuSE / Novell service packs

2008-01-02T11:34:00.000+11:00

I've had Red Hat Enterprise Linux and Ubuntu products before, and occasionally they have "Service Packs". Essentially, some time the vendor decides "gee, we've shipped a lot of patches. Lets respin the CD". Apparently this isn't what Novell / SuSE do.

You see, when Novell / SuSE ship a "service pack", they helpfully stop all machines which don't have that service pack from taking any updates. And you have to go through a long winded "upgrade to the service pack" process (documented here, I used the "rug" method), after which you can once again resume normal service of getting patches.

So that's why my updates haven't been working for a while on my SuSE servers.

Mac OS X v10.5 and Java 6

2007-11-30T23:56:00.000+11:00

So, it's well documented on the web that it was expected that Apple would ship Java 6 with Mac OS X v10.5 (Leopard) and didn't. For those who have been living under a rock, they shipped Java 5, despite Java 6 existing for Windows, Linux and Solaris users for well into the "years category" now. There has been quite a lot of heated action on forums.

But the thing is that most of those people can live with Java 5 - it doesn't make a huge difference to them. It does to me - my main development machine is my MacBook, our software is written in Java, and we upgraded to Java 6 not long after it shipped. About when the Apple JDK 6 beta shipped, actually.

Anyway, I've been looking around the web for evidence that the beta (that Apple have helpfully removed from their website without replacing it with another version) runs on OS X v10.5, in the hope that I can continue working on my MacBook with the old beta. I've done the upgrade, and for those who want to know - no, you can't run the JDK 6 for OS X v10.4 beta on v10.5 - the installer won't let you install it.

So, we'll have to see next week whether we actually use any "JDK 6 only" features when I'm forced to use JDK 5, or if I'll have to "downgrade" to OS X v10.4 or even a PC with Linux.

XT Forester

2007-10-17T01:21:00.000+10:00

So, with the Pulsar SSS well gone (only took a week to sell), we've since purchased a Subaru Forester XT. It's a 2.5L Turbo, all wheel drive mum-mobile, which my wife quite likes. It is a bit rolly-polly (particularly compared to my WRX STi), but it's a good tradeoff between practicality and performance, particularly at the price they go for.

So if you're looking for a practical family car and don't want to spend big bucks, but want something that's still a bit of fun to drive, go test drive an XT Forester.

GTiR Pulsar conversions

2007-08-26T10:07:00.000+10:00

At the moment we're selling my wife's 2000 Nissan Pulsar SSS. It's never been modified, and is listed on carsales.com.au at the moment. So I was just looking through the other ads, and it's amazing how many "GTiR conversions" are for sale.

For those who don't know, there was an all wheel drive, turbocharged Japan-only model called the GTiR, of which there are quite a few here in Australia brought in as second hand imports from Japan. A friend of mine had one, and had it up for sale for around $14000.

Now, the SSS is worth about $10000 - $11000 unmodified, and is front wheel drive, and doesn't have a turbo. Now, these conversions; the GTiR engine must cost at least $4000 to put in, plus extra for the turbo and exhaust - why on earth wouldn't you just buy the real thing for the same price or less?

Poetry and Linux

2007-08-15T23:47:00.000+10:00

I was browsing KernelTrap today, and came across a report on a thread of Rusty Russell writing documentation in poetry. It's worth the read - this is funny stuff. The funniest of the lot for mine was one from Rusty:

There was a poetic infection
Which distorted the kernel's direction,
The code got no time
As they all tried to rhyme
And it shipped needing lots of correction.

Now that's just all class, isn't it?

Cleaning out the photo collection

2007-08-05T19:24:00.000+10:00

About two years ago my old Minolta "point and shoot" camera, which I paid $1000 for around the turn of the century. I sent it back once to be fixed (zoom was stuffed), and it cost $500 to fix. Two months later it was stuffed, so I decided to replace it. My thinking was "bugger it - lets buy something that doesn't suck".

Canon had not long released the EOS 350D (sold as Digital Rebel XT in some markets), an 8MP digital SLR camera aimed at the enthusiast market. At the time I didn't know much about photography at all, so it was an ideal camera. Cost about $2100, including two lenses - an 18-55mm, and a 75-300mm kit lens. Of course, the current equivalent kit from Canon costs under $1500, and if you're looking for a camera, it's probably a good pick.

The bit I didn't realise was how average the lenses are that are in the kit. Earlier in the year I started doing some photography courses with Ben from Fusion Photography, who's a real passionate professional wedding photographer. I think we've done about 12 hours worth of lessons with him, and it's amazing the difference it has made to the photos I'm taking. A mix of skills learnt from Ben and better lenses (my latest purchase is a 70-200mm L-series Canon lens) has made quite some the difference.

Earlier I ran out of disk space on my laptop, and needed to clear some space, as I downloaded the trial of Adobe Photoshop CS3 for Mac (Intel). Over one third of my disk space was photos, so I decided to clear them out. First time I'd looked at some of them since 2005, and there were some shockers there which I had once thought were ok. Lots of them were so dark, and it made me realise how good the f2.8 L-series lenses were compared to the f4-5.6 lenses you get in a kit. Might put my old lenses up on eBay, and just get rid of them.

Gran Tourismo 4

2007-07-15T13:46:00.001+10:00

Going back about six months, Sony's Playstation 3 had yet more delays, and Microsoft had released the XBox 360. As a result, Sony reduced the PS2 to $186, and all but the absolute latest games to about $30. Seemed like good value - I'm not paying $600 for a console, and $100 per game.

So anyway, I went out and got myself a PS2, with a steering wheel (Logitech Driving Force - $150), with Gran Turismo 4, a few Rally games, and one or two others. Initially, I couldn't get into GT4 - it felt like MS Flight Simulator - modeled reality, but wasn't very interesting a game.

Anyway, more recently, I've started playing it again. I don't know what is different this time, but I've found out why people love this game. Sure, it's a great simulator, but you can choose your own way through the game. If you like American trucks, you can buy one of them and take on the Truck series. If you like turbocharged Japanese cars, buy one and take on that series.

And I realise - when GT5 is released in 2008, that's about the only thing that will make me want a PS3. But that means a new TV (to support High Definition), a new steering wheel (why can't I just use my PS2 one?), and a console, plus the game. Not sure that I'll bother - maybe I'll wait until PS4 is due, and the PS3 is $186.

Eclipse 3.3

2007-07-05T22:20:00.000+10:00

We use a lot of open source Java software at work, and we seem to spend half our lives in Eclipse. Not only do we use Eclipse as our development environment, but we use their Java GUI widget set (SWT/JFace) for our user interface.

So it was a nice suprise to see that Eclipse 3.3 has finally been released. I've been using pre-release versions of the SWT/JFace destined for Eclipse 3.3 for months now in our product, and on the Mac platform (which is what I use as my desktop), as I found it to be more stable and layouts to be more compatible with Linux and Windows implementations.

So here's to the Eclipse people - good job guys, thanks a lot.