Technical Musings

ObSrv bug fixed (empty feeds)

2011-12-19T07:45:00.000+10:00

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Over the last few weeks ObSrv was often returning empty feeds.

I’ve fixed this bug.

If there are any further problems, please let me know.

Big Black Holes

2011-10-10T18:06:00.000+10:00

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Baby Black Hole by Nasa

This is an open question to anyone who might understand astrophysics better than me (which is probably most of the human race).

Assume there is a really big black hole. So large, in fact, that its event horizon is more than one light-year across. If you do the sums, the gravitational force near the event horizon of such a large black hole would roughly be about 1g – the same as what it is on earth.

Imagine coming close to this event horizon in a spaceship. It would be easy to accellerate away – after all, the gravitational force in the vicinity is only 1g. So any imaginary spaceship capable of escaping the gravity of earth – if it were near the event horizon of this super massive black hole, would be able to escape its gravity.

One of the horrors you normally hear about black holes is the tidal forces that would “tear you apart”. This is caused by the difference in gravitational forces as you move closer to center of gravity of the black hole. The same thing happens near neutron stars. Your head is being pulled with a lesser force than your feet. So you get “stretched”. But in our thought experiment, the centre of gravity of our supermassive black hole is over a light-year away. My head won’t feel any different amount of attraction than my feet would. There would be no noticeable tidal forces to speak of.

So imagine you’re sitting in your late-model spaceship, orbiting just outside the event horizon of this super-massive black hole. You don’t feel any tidal forces, and the black hole is exerting a similar gravitational attraction on your vessel as what you’d experience orbiting the earth.

Apart from the huge black sphere blocking half of the sky, and the strange lense-like effect of light bending as we look across the horizon of the black hole to the numerous stars in the distance, there’s nothing to be afraid of is there?

My point is it would only take a reasonable amount of thrust to move our vessel away from the black hole.

BUT… imagine as we sit near the event horizon, we move slowly towards it until we have moved INSIDE it. What would happen? What would we experience? My meagre understanding of physics leads me to think that the escape velocity just outside the event horizon would be slightly less than the escape velocity just inside the event horizon.

So the burning question then is why couldn’t you escape from this super-massive black hole, having visited the forbidden area just inside the event horizon? The gravitational attraction at this distance would be small enough for our ship to thrust away.

And this leads me to another question. If the gravitational force near this super-massive event horizon is about 1g, why couldn’t light escape from an object just inside the event horizon? And if light could escape, would there even be an event horizon? The “Black Hole” appearance of this thing is based on the assumption that no light can escape from it because the required escape velocity exceeds the velocity of light.

So please help me. I obviously know nothing about black holes. I must be making an incorrect assumption. I don’t mind asking stupid questions, and am hoping that a patient genius will take the time to reply and explain where I’m going wrong.

Thanks in advance

ObSrv – Appropriate Images Please

2011-06-28T09:30:00.000+10:00

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I’ve added a mandatory “Safe Search” filter to all images served up by ObSrv.

To most users, you won’t notice any difference, but the problem was that some people were using ObSrv to generate adult images, which got me in trouble with Google Adsense.

This is a business decision, not a moral one. Using ObSrv to generate adult images would get my Adsense account cancelled. No Adsense income = No ObSrv. Everyone would lose. So the simplest solution I could find was to block anything that didn’t pass the Google “Strict Safe Search” test.

If you find your image feeds aren’t generating images any more, please consider using less adult-related search terms.

Low-res Brain

2011-01-19T14:05:00.000+10:00

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Thought experiment.

Close your eyes and imagine a clock face with hands and numbers.

Imagine the clock face as a whole. Try not to think of just parts of it.

In your minds eye can you see the individual numbers on the clock face all at once?

I can’t.

I have to “zoom” in to each part of the clock to see all the numbers. I can’t see them all at once.

If the brain can’t do this while we’re awake, then it’s no wonder we don’t have vivid details of items when we’re asleep and dreaming.

If our brains imagery has such low resolution, why do we seem to have such hi-resolution memories?

Maybe it’s different for you. But that’s how it is when I try it.

This whole experience helps me understand how my brain visualizes things. It’s not like the “Pictures” folder on my computer. I don’t store high-resolution pictures in my head. I think it’s more like a short-hand way of reconstructing a picture. Without realizing it my brain says “A clock is a circle. And it’s got numbers around it from 1 to 12. And it has hands. And it ticks”.

Perhaps it’s like that for someone’s face as well? Do you know every freckle, mole or scar on your partners face? When you think about it, how much detail of someone’s face do you actually remember? I think perhaps we actually store a low res “caricature” of a persons face in our brain, and when we see that person, we match what we see of their face with the low res memory of it, and somehow our brain can recognize that the two things represent the same person.

I think our physical perception of reality is a lot less detailed than we realize. When we look at a page in a book, there’s only a small circle of our vision that can actually see fine detail – about the width of our thumb held at arms length. If you hold your thumb in front of a book held at arms length, and focus on your thumb, you’ll find it almost impossible to read the book. That’s because the Fovea (the bit that sees detail) in your eye only occupies a small part of your Retina (the bit that actually sees things). But our brain manipulates us to think that we can see everything in detail, because our eyes dart around, and our brain puts all the jigsaw pieces together.

So next time you’re certain you saw something, remember that what you saw, what you thought you saw, and what you remember seeing are all totally different!

Isn’t the brain an amazing thing?

Problems Activating and Updating Windows 7 behind an Endian Firewall

2010-09-29T04:46:00.000+10:00

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I have had problems Activating and Updating Windows 7.

I have an Endian firewall appliance.

The main error I was getting was 0×80072EFD – unable to connect.

For me, the solution (after hours of heartache) was simple:

Go into Control Panel / Network and Internet / Internet Options / Connections tab / LAN Settings,

UNTICK “Automatically detect settings” and press OK.

Activation then works.

Updates then work perfectly.

Sorry – I’m not sure why this happens. I suspect it’s a bug in Endian version 2.2 which is fixed in later a version, probably relating to the internal Endian Proxy server which in my case is disabled anyway.

I hope this helps someone.

Many thanks to my son, Lachlan, who also had this problem, and figured out how to fix it after several days of heartache.

ObSrv Performance Improvements

2010-02-25T22:28:00.000+10:00

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I’ve improved the load speed of the ObSrv home page. Sometimes it would take a long time to load.

I’ve also improved the speed of the image feeds. It still can be sluggish at times – that’s because it’s heavily used, but to counteract this, the Image Feed will ignore requests from the same computer if they come more frequently than about once every 3 or 4 seconds.

For most people this won’t be a problem, and the only time you really notice delays on the Image Feed is if you try and display it in your browser.

If site performance is still an issue for you, please let me know.

Around Pine Rivers

2010-02-10T11:58:00.000+10:00

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Here’s a brief description of each of the photos in the “Around Pine Rivers” theme for iGoogle.

If you’ve got any suggestions, corrections or improvements, please let me know.

Click on the images for a larger view.

Bell’s Scrub is the only remaing parcel of virgin lowland vine rainforest in the Pine Rivers district.

See http://blog.neilennis.com/index.php/bells-scrub-lawnton/

Some of the stunning late afternoon views in my street.

see: http://blog.neilennis.com/index.php/everyday-beauty/

Fleeting glimpses of childhood on the North Pine River.

See http://blog.neilennis.com/index.php/fleeting-glimpses-of-childhood/

Christmas Beetle.

See: http://www.flickr.com/photos/magictyger/sets/72157603351606109/

Wikipedia Article: http://en.wikipedia.org/wiki/Anoplognathus_pallidicollis

Lightning in the Gum Trees.

See: http://blog.neilennis.com/index.php/lightning-in-the-gum-trees/

Ebert Family Vineyard.

See: http://blog.neilennis.com/index.php/echoes-in-the-vineyard/

Stephen Lawn Park.

See: http://blog.neilennis.com/index.php/nuts-about-history/

Lake Samsonvale.

See: http://blog.neilennis.com/index.php/lake-samsonvale-2/

Wikipedia article: http://en.wikipedia.org/wiki/Lake_Samsonvale

South Pine River near the site of the old Normanby Rum Distillery.

See http://blog.neilennis.com/index.php/bikes-rivers-old-rum/

Yebri Creek.

See http://blog.neilennis.com/index.php/exploring-on-sunday/

Sunset on the North Pine River.

See: http://blog.neilennis.com/index.php/sunset-on-the-north-pine-river/

Lake Kurwongbah.

See http://blog.neilennis.com/index.php/cycling-by-the-lake/

Here’s a wikipedia article: http://en.wikipedia.org/wiki/Lake_kurwongbah

ObSrv: Why only 21 images at a time?

2009-11-16T18:23:00.000+10:00

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Aaron asked a good question they other day.

Why does ObSrv only ever return 21 images at one time?

I thought it was a bug in my code, but it’s not. ObSrv pulls images from Google Image Search, and Google only ever returns 21 images in one go.

But this is not a problem. The images are embedded into a MediaRSS feed. That feed is cached for a maximum of one hour. After this time if you request the same feed, ObSrv will search again, but will only show images that it didn’t show last time. In the unlikely event that it runs out of images, it starts searching from the beginning again.

So although there’s nothing I can do about the 21 images at a time issue, it’s not a major problem because you will get more images after the feed refreshes – but remember, to save server resources (and to stop Google from banning me) it waits an hour between doing searches on the same terms.

On Yer Bike!

2009-09-05T12:04:00.000+10:00

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View Larger Map

I took Steve and Harrison on a bike ride this morning, along the North Pine River, up to Lake Samsonvale, and then back along the North Pine Rover.

It was a hoot! A little bit slower than normal, because Harrison is only 9 and his bike is a bit worse for wear. But it was fun all the same.

And I got to try out a new program for my Nokia N95 mobile phone. Nokia Sports Tracker Uses the inbuilt GPS on the phone to record speed and height info. While you’re cycling, your N95 acts like a speedo, and odometer, showing you all the vital stats. But when you get home, you click the button, and upload the data to sports tracker.

The really cool thing is that if you take any photos with the phone on your journey, it will upload and geotag them.

So the map on the left here is where we went. You can drag and zoom it if you want more detail.

But the fun part is that the data is also uploaded to the Sportstracker community. Here’s a link to the data for our ride today. If you tick the “altitude” box, you can see every hill, and how fast we were going.

The thing I like most about this technology is that it adds to the fun of getting out and exercising. At times I’ve found it hard to overcome my inertia to regularly exercise. In regards to exercise, if it makes me think “Oh yeah! I want to do that again!” then I think it’s a great thing.

Oh – and you can use Sports Tracker for running, walking, skiing, rowing – whatever floats your boat.

P.S. I’ve ordered a mounting bracket to attach my phone to my handlebars. Till that arrives, I’m using some of Lilly’s hair ties

Flickr RSS Feeds. Too big, too small

2009-08-30T12:04:00.001+10:00

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In this article about using slideshows in wordpress I showed you how to embed slideshows in Wordpress blog posts and sidebars using the Google Ajax Feed API.

I prefer to use this facility to pull in Image feeds from Flickr.

The problem with the images in these feeds is that they’re either too large or too small.

The MediaRSS specification has a tag which lets you have a thumbnail image in your feed. That’s great, but the image size of the thumbnail is 75×75 pixels, which is useless for a nice looking slideshow. It ends up looking terribly blurry with no detail.

The Google Ajax Feeds API tries to get around this by letting you specify a “thumbnailTag” in the slideshow options object. Basically, you set this to “content” to tell the API to look for the image in the “content” section of the feed, rather than the section. This is also great, but the problem is that Flickr uses the LARGE (or even worse, ORIGINAL) image size in this section. So you get nice large detailed images in the feed, but they’re so large that they take ages to load, and your slideshow sits there for ages saying “Loading….” while it grabs the huge images and chews up your audiences bandwidth.

So I wrote a simple PHP screen scraping utility which grabs the Flickr feed, and changes the ImageUrl…_L.jpg to ImageUrl….M.jpg – in other words, it modifies the feed to include the medium size image rather than the large size.

Medium sized images are fine for slideshows, and they load quite quickly.

Here’s the PHP code:

<?php date_default_timezone_set('UTC'); $uri=""; $first_var = "1"; foreach($_GET as $variable => $value) { if ($variable == 'uri') { $uri = $uri . $value; } else { $uri = $uri . "&" . $variable . "=" . $value; } } header("Content-Type: application/xml; charset=ISO-8859-1"); $ch = curl_init() or die(curl_error()); curl_setopt($ch, CURLOPT_URL,$uri); curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1); $data1=curl_exec($ch) or die(curl_error()); $data1=str_replace("_s.jpg","_m.jpg",$data1); $data1=str_replace('height="75"', "",$data1); $data1=str_replace('width="75"', "",$data1); echo $data1; echo curl_error($ch); curl_close($ch); ?>

Just save this in a file named FlickrRSS.php in the top folder of your wordpress directory. Then instead of using your flickr RSS feed, pass the feed as a query parameter to the PHP utility.

You’ll need to change the <> tags in the file to <>.

So if your feed URL was this:

http://api.flickr.com/services/feeds/photos_public.gne?id=8575807@N07&lang=en-us&format=rss_200

Use this instead

http://YourBlogUrl/FlickrRSS.php?uri=http://api.flickr.com/services/feeds/photos_public.gne?id=8575807@N07&lang=en-us&format=rss_200

This will change the tag to point to the lager sized image, so your slideshows will load quickly, and look nicer

Cool technology

2009-08-02T18:37:00.005+10:00

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Lilly came in to my office the other day. “Dad I have to go out now. Can you get the TV to record my favourite show in an hour”.

“Hmmmm????”, I replied in typical pre-occuipied father mode.

But she had an intensity in her eye that made me realize I ignored this six year old at my peril, despite my displike of leaving my desk while in the middle of solving a problem.

Happily, I didn’t have to get up from my chair. I just logged in to IceTV, found the program she was interested in, and told my PVR to record it via the website. My PVR is a High-Definition Beyonwiz DP-S1. It’s wireless, but I’ve wired it in to the house LAN so we can watch movies from our D-Link DNS323 1TB NAS

We also have an older Topfield 5000 PVRT. It’s only standard definition, but the cool thing about it is that it has an open programming interfacem , so a lot of people have written their own software to get it to do cool things. One application I added to it was ToppyPC by John De Angelis. It has a program called “TWIN” which adds a web page to your Topfield PVR. So you can set timers, and record shows, like IceTV lets you do with the Beyonwiz. ToppyPC needs another utility to run – an FTP server (ftp4t by Aldarin) which runs on a PC which I connect to the Topfield via a USB cable.

All this technology is both good and bad. It’s convenient, but I don’t get the exercise I need going up and down stairs to program the PVR!

But at least I don’t have an angry six-year-old to contend with!

Some amazing facts

2009-07-27T16:24:00.001+10:00

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I just watched this fascinating Youtube video. The world is an amazing place!

My Inbox

2009-07-17T14:17:00.001+10:00

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Neil's empty inbox - a rare event

Isn’t this beautiful?

I haven’t seen an empty inbox for years, and I love it! When it’s full I feel like I have the cares of the world on my shoulders. But when it’s empty, it’s like I’m making progress. Even if it might be illusory, I like that feeling.

So I’m going to persist in my strategy which can be described simply as:

If it’s junk, get rid of it.

If it’s someone elses problem, forward it.

If it’s worth reading, read it now, then delete it.

If it needs more info, request more info and delete it.

If it needs acting on, then act on it now, then delete it.

Slideshow from RSS for Wordpress

2009-07-13T11:56:00.001+10:00

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Loading…

It took me hours to find, but the easiest way I found to build a slideshow from a MediaRSS feed and add it to a WordPress blog was using the Google Ajax Feed API.

There are a few plug-ins that are supposed to work with WordPress, but I didn’t like them because they were really limited, or didn’t work on an IIS hosted blog. Good old Javascript, although it’s verbose, works fine.

That’s what I’ve used on this blog. Have a look at the slideshow on the lower right. It’s generated by the Google Ajax Feeds API.

If you don’t like getting your hands dirty with JavaScript, the best Flash based slideshow generator I know of is at VuVox.com. That’s what I use for some of the ObSrv examples of slideshows here.

The beauty of building a slideshow from an RSS Feed is that you don’t need to have the images on your own site, and the content updates continually as more items are added to the feed.

Of course, sometimes it’s hard to find a good feed. That’s where ObSrv.com comes in, because it can generate a feed from a google images search.

So when you use the Google Ajax Feed API and ObSrv.com you can make a slideshow of any topic you’d like. The one on this site is for “Information Technology”.

And just to make this post pretty, I thought I’d include a slideshow of the most recent ten pictures from the Creative Commons group on Flickr

We've Moved!

2009-07-12T12:59:00.004+10:00

This blog has moved!

The new address is

http://tech.NeilEnnis.com

Please update your browser and RSS reader to the new links. All of my existing articles have moved too.

I'm now using WordPress as my blogging platform, and really like it.

If you've got any comments or suggestions, please let me know.

Using Twitter

2009-05-21T09:14:00.002+10:00

A few friends have asked me to explain twitter.

Rather that re-invent the wheel, I thought I'd upload a few links that explain what it's all about.

1. The official Twitter Help Resources / Getting Started

2. How to Use Twitter Without Twitter Owning You - 5 Tips (Tim Ferriss)

3. How to Use Twitter (Darcy Logan, includes great short video)

4. Newbie's guide to Twitter

5. Twitter Fan Wiki (Sort of like Wikipedia for Twitter)

6 HashTags

Actually HashTags deserve a post all of their own. I'll post something about that later.

I hope these links help. The bottom line for Twitter I think is to follow people who have something interesting to say. Don't just follow anyone, because then the interesting comments will get drowned out with "noise".

And the converse is that it's important make your posts useful. Say stuff that will be interesting to people who follow you. Here's some examples of people who post some really great twitter articles:

@Astro_Mike An Austronoaut tweeting from orbit
@tferriss Author and blogger on lifestyle design
@612brisbaneMy local ABC radio station

Oh, and if you're interested, I'm on twitter as @NeilEnnis

ObSrv: Server Problems Fixed

2009-03-22T11:31:00.002+10:00

I apologise for the unavailability of ObSrv.com over the last few days.

Our server failed, so we bought a new server, which also failed.

Not being one to give up easily, I've been on this issue since Friday lunchtime, and am relieved to say that as of about 10pm last night, everything is now working fine.

On the bright side, we have a larger, faster server so things should run much better than before.

RSS Feed Do's and Don'ts

2009-02-25T09:33:00.003+10:00

To the right you can see a screen shot of three RSS feeds as seen on my iGoogle page. Two of them are good, one of them is not so good. Can you tell the difference?

They're all really specific in nature. The first one just shows breaking news as reported by the ABC. The second shows recent posts made be people about cruises in Australia via the CruiseCritic.com message boards, and the third shows new posts to the "General Cruise Discussions" section of the OzCruiseCritics message boards.

With the ABC feed, whenever there's a new story, it appears at the top of the list, pushing older stories off the bottom of the list.

Same with the Cruise Critic feed (the 2nd one). As a new post is received on a particular subject, that subject goes to the top of the list, pushing older ones off the bottom.

The problem with the third feed ("General Cruise Discussions") is three-fold:

1. The name of the feed doesn't do OzCruiseCritics justice. Anyone casting a quick glance at the feed doesn't know where it's from. With the first two feeds on this example, it's quite plain who's supplying them, but not the third feed.

2. The discussion topics are not formatted properly. The name of the feed is repeated in each of the item descriptions. E.g. you see "General Cruise Discussions :: Re: Queensland Cruise" and "General Cruise Discussions :: Re Snorkelling". This is redundant. We already know what feed the item is coming from by looking at the title of the feed. Each of these items should have a more concise description. In this case they should be "Queensland Cruise" and "Snorkelling".

3. You can't see it from the picture, but take my word for it, whenver someone replies to a topic on the OzCruiseCritics feed, it generates a new feed item. So if I was to reply to the "Snorkelling" discussion, the feed would end up looking like this:

General Cruise Discussions :: RE: Snorkelling
General Cruise Discussions :: RE: Queensland Cruise
General Cruise Discussions :: RE: Snorkelling

I think that is crowded and difficult to read. What should really happen is that if an item is updated, it goes to the top of the list, and the old version of that item is removed from the list. So the feed should look like this:

Snorkelliung
Queensland Cruise

These suggestions might seem pedantic, but the whole aim of RSS is to get your content read. Whish means the info needs to pack as much punch as possible, with as little clutter as possible. The reward for this is that your message gets out, more people hear what you say, and you get more traffic to your site.

ObSrv: Improved image search

2009-02-04T13:45:00.003+10:00

I just fixed a couple of minor bugs which were preventing ObSrv from serving up images based on advanced google image searches.

They should be working ok now.

If you still have any problems, please let me know or reply to this post.

ObSrv: Getting an RSS feed from ANY site with images

2009-01-30T13:37:00.002+10:00

I mentioned earlier that I'd modify ObSrv to be able to generate an RSS feed from any site that has images.

I didn't realize it, but it already does this.

Just key in the search words, followed by site:yourdomain.com

For example, if you want a feed of all images of the planet Saturn from Nasa.gov, just type in:
Saturn site:nasa.gov

Or for a feed of all images of Antarctica from NationalGeographic.com, type in:
Antarctica site:nationalgeographic.com

How cool is that?

ObSrv: Some example image feeds

2009-01-29T10:04:00.005+10:00

Here's some slideshows built on image feeds from ObSrv. If you've got some you'd like to show the world, please send an email to mail {at] ObSrv [d0t} com and I'll be happy to showcase it here for you.

ObSrv: Watching the World

2009-01-25T12:14:00.007+10:00

I've just completed a project called "ObSrv" which will convert Google Image Searches into MediaRSS compliant RSS feeds.

If you don't know what an RSS feed is, perhaps you should read this, or this. I love RSS because it's an easy way to let other people know what you're doing, and to find out news that is of specific interest to you. This blog (like almost all others) has an RSS feed. Most news sites and picture sharing sites have RSS too. This makes it easy for you to show their content on your website, or to view their content in an RSS reader.

If you don't know what MediaRSS is, you might want to read the specification. Basically, it's for a special type of RSS feed that contains media, such as pictures, video, and music. These feeds are cool because pictures, videos and music are much more entertaining than plain text. You can do more with them. For example, there's a slideshow on the right hand side of this blog that updates every few seconds with pictures of hi-tech gizmos. It's based on a Media RSS feed.

My favourite Media RSS application is John's Background Switcher. It updates the wallpaper on your computer desktop with pictures from a Media RSS feed.

My only problem with Media RSS is that the biggest source of images on the web (Google Images) doesn't serve up their image searches as an RSS feed. Which means that while you can search for images at google, you can't automatically feed them into a media RSS application.

That's where ObSrv comes in. It converts a Google Image search into a Media RSS feed.

Here's how:

Go to http://obsrv.com/

Type a few search words in the box. (Hint. If you want, do an advanced search in Google Images, and copy the Google Images URL into the box instead).
Press ENTER or click on the "GO" button.

ObSrv will give you the link to your feed.

Click on the link to open the feed in a new window, or copy the URL for the feed from the textbox.

Here's some links to some applications that you can use with RSS Image Feeds:

John's Background Switcher (Windows desktop background switcher)

Vuvox (Slideshows)

Feed Reader

RSS Popper

What's Next?

I'll be adding functionality to ObSrv as time permits. My next task is to get it to convert any webpage containing images into an RSS Image Feed.

Outlook not showing embedded images

2008-09-08T09:29:00.002+10:00

Sometimes when I received an email in Outlook with an embedded image, the image would not display, but I'd just see a white rectangle with a small red "X" in it instead.

This was nothing to do with the outlook security settings.

To fix the problem, I deleted the following registry key:

HKEY_CURRENT_USER\Software\Microsoft\Office\11.0\Outlook\Security\OutlookSecureTempFolder

After I deleted it, I restarted outlook, and my images now appear fine.

Schizophreinc Blogs!

2008-09-01T21:37:00.007+10:00

I have a schizophrenic blog. Some days I upload copies of postcards that I receive. Other days it's info about migration to Australia in the 60's. And then it might be some photos of family and friends.

So it's a bit of a mixed bag.

Which is fine by me. My attention gets pulled all over the place, and I get interested in lots of different things. A bit like Homer Simpson walking through a shopping mall :)

But it could make life hard for my readers, so I recently added a little Javascript widget that makes the blog change its appearance depending on what interests you. Coupled with judicious use of blogger labels, it works wonders.

It's the same blog, but it changes shape depending on how you get to it.

Have a look at these two different links to see what I mean.

First if you're interested in Postcards go to the blog via the URL: http://neilius.blogspot.com/search/label/Postcards?pcd=1.

Second if you're interested in Ten Pound Poms go to the blog via the URL: http://neilius.blogspot.com/search/label/Ten%20Pound%20Poms?tpp=1.

(Hint for the uninitiated "Ten Pound Poms" were migrants who came to Australia from Britain between 1950 and 1971).

There are two cool bits to this.

The first is that you get a totally different set of links at the top of the blog depending on how you view it. I do this by adding some query string parameters to the URL. (The "?pcd=1" or "?tpp=1" parts of the URL).

Secondly, using labels in the URL lets me control what articles appear when you visit. (That's what the "/search/label/..." bit of the URL is all about).

You might think using query strings on your URL is a messy way to get to your blog. But it's really easy to set up a domain and (using something like ZoneEdit's "webforward") point that domain to a more complex URL.

For example, http://TenPoundPoms.com and http://Postcards.NeilEnnis.com both point to the same blog, but I've used ZoneEdit to add different parameters to the URL query string.

A small Javascript widget at the top of the blog looks at the query string, and decides what sort of links to display. Basically it's saying "If you've come here to look at postcards, I'll show you some postcard links. But if you're interested in Ten Pound Poms, then I'll show you some different links instead.

Here's the code. The Orange section is a javascript function to pull the query parameter out of a url. The Green section controls what gets displayed when people are interested in "Ten Pound Poms". The Blue section is what gets displayed when people are interested in "Postcards".

<script>
function gup( name ){ name = name.replace(/[\[]/,"\\\[").replace(/[\]]/,"\\\]"); var regexS = "[\\?&]"+name+"=([^&#]*)"; var regex = new RegExp( regexS ); var results = regex.exec( window.location.href ); if( results == null ) return ""; else return results[1];}
</script>
<script>
var tpp_param = gup( 'tpp' );
var pcd_param = gup( 'pcd' );
if(window.location.href == 'http://neilius.blogspot.com/search/label/Ten%20Pound%20Poms')
tpp_param = '1';
if(window.location.href == 'http://neilius.blogspot.com/search/label/Postcards')
pcd_param = '1';
if(tpp_param == '1')
{
document.write('<div id="tpp-info" class="sidebar section">');
document.write('<h2 class="title">Ten Pound Poms</h2>');
document.write('<a href="http://neilius.blogspot.com/search/label/Ten%20Pound%20Poms?tpp=1">Home</a> Ten Pound Poms | ');
document.write('<a href="http://neilius.blogspot.com/2008/07/about-tenpoundpomscom.html?tpp=1">About</a> Ten Pound Poms | ');
document.write('<a href="http://neilius.blogspot.com/2008/08/links-for-ten-pound-poms.html?tpp=1">Links</a> for Ten Pound Poms<br/>');
document.write('<a href="http://neilius.blogspot.com/2008/08/migrant-ships.html?tpp=1">Migrant Ships</a> - How we got here<br/>');
document.write('<a href="http://neilius.blogspot.com">Musings</a> - Back to the main blog');
document.write('</div>');
}
else if(pcd_param == '1')
{
document.write('<div id="pcd-info" class="sidebar section">');
document.write('<h2 class="title">My Postcards</h2>');
document.write('<a href="http://neilius.blogspot.com/search/label/Postcards?pcd=1">Home</a> - My Postcard Blog | ');
document.write('<a href="http://neilius.blogspot.com/2008/05/about-my-postcards.html?pcd=1">About</a> My Postcards | ');
document.write('My Postcrossing <a href="http://www.postcrossing.com/user/Neilius" target="_blank">Profile</a><br/>');
document.write('<a href="http://postcrossing.com" target="_blank">Postcrossing</a> - A great way to send and receive postcards<br/>');
document.write('<a href="http://flickr.com/photos/magictyger/sets/72157604961465429/" target="_blank">Postcard Collection</a> at Flickr<br/>');
document.write('<a href="http://neilius.blogspot.com">Musings</a> - Back to the main blog');
document.write('</div>');
}
</script>

More algebra

2008-07-02T11:10:00.002+10:00

A couple of years ago, in this post I published the formula for calculating loan repayments based on rate, PV, FV and interest rates etc.

I mistakenly said that you couldn't arrange the formula to give an expression which would calculate the TERM given the other values.

I was wrong.

Here's the formula:
NPER = LOG((PMT*(1+RATE*TYPE) - RATE * FV) / (PMT*(1+RATE*TYPE) + @RATE*PV)) / LOG(1+RATE)

FV is the "Future Value" of an investment assuming an initial investment (PV), constant repayments (PMT) and a constant interest rate (RATE) over a fixed term of months (NPER). When "TYPE" is zero, loan repayments are made in advance. When "TYPE" is 1, loan repayments are made in arrears.

It yields a non-integer result. The result should be rounded up to the next highest integer, with the value of the final repayment reduced.

If I get time I'll post a formula for the final repayment later.

Where did my money go?

2007-12-22T19:32:00.000+10:00

www.MoneyTracker.com.au is a great site that lets you track the location of your bank notes after you spend them.

Basically you go to the money tracker web site, and enter the serial number of any bank notes (cash) you have. Then you just spend them like you normally do. Eventually, someone else will get the note, enter it into money tracker which then notifies you of the new location of your bank note.

This fascinating idea was inspired by the US website http://wheresgeorge.com/ which lets you track U.S. bank notes.

Now all we need is some sort of machine that can help us get our money back after we spend it :)

Sir Arthur C. Clarke 90th Birthday Reflections

2007-12-16T22:01:00.000+10:00

Scince fiction writer and visionary Arthur C Clarke turned 90 on Sunday.

Best known for his blockbuster "2001: A Space Odyssey", he also wrote numerous other books and short stories.

I've devoured most of his works since I was 11 years old, amd marvelled at Clarke's optimistic vision of the future, and what we could achieve as a species. He made the future exciting. I couldn't wait for it to happen, and still can't :)

I hope you stay around till you're at least 100, Sir Arthur. We need more optimistic vision like yours.

What's cool, what's not?

2007-10-07T13:58:00.000+10:00

Technology is cool.

There is so much new cool stuff you can do these days.

Here's just a few:

ShipWatcher - a new website I created that lets you look at the webcams of cruiseships, view their progress on a map, and take photos of ships you like. Every hour ShipWatcher picks webcams that it thinks are "interesting" and take a couple of photos, automatically uploading them to....

Flickr - a fantastic service, from Yahoo that lets you share photos with other people, place them on a map, group them into sets and collections, pool them into groups with other people, and even track the type of camera that took the photo - to help you choose your next camera. I even used Flickr to share some great looking Photo Mosaics that I generated with...

Andrea Mosaic - a clever little utility which lets you generate mosaic pictures like this one I did, from pools of photos that you might have. In fact, if you have large pools of photos, you might be interested in...

Photosynth - amazing new technology from Microsoft that pools photos, organizes them in relation to each other, and lets you view a 3-d model of the real world, by aggregating thousands of photos. This really has to be seen to be beleived. I have a copy of it on my main machine which runs....

VMWare -fantastic software that lets you build "virtual" computers. You can configure a number of different types of computers with different amounts of memory, diskspace, networking abilities, each of which can run a different operating system like Windows XP, Linux, Vista, DOS, and run them all at the same time. You can even get your virtual machine to take a snapshot of itself. Do some risky stuff, and then if you don't like the result, rollback your machine to the state it was in when the snapshot was taken. Great for demos, when you want the demo to revert back to its previous incarnation when you're finished. If you have a laptop, copy your virtual machine from your desktop to your laptop, and it's ready to go. Everything on the laptop is the same as when you last used it on your desktop. So easy to backup too. Just copy the virtual disk (one file). I use VMWare to do all my software development, including a cool web development tool called...

Iron Speed Designer - easy to use software that lets you quickly generate websites based on any existing SQL, Oracle or Access database. I've never developed websites before, and Ironspeed made it easy to look like a pro. Great stuff.

It seems things just keep getting better. Life gets easier for us. We can do more, in less time.

BUT. Some things aren't cool. They make life harder. They suck. Even some things that are cool can suck. For example....

Iron Speed Designer - although a great tool, decided that they didn't like people using their software inside a virtual machine. Aparently some people were using the flexibility of virtual machine software such as VMWare to defeat the copy protection mechanism. So the folks at Ironspeed decided they'd put a limitation in version 5 of their software that makes it refuse to run on a virtual machine.

You may think "so what?". But think about what this means. If you've got your entire development environment inside a virtual machine. And one of your development tools stops working in that machine. What do you do? Uninstall it and move it to a real machine I suppose.

But I use MS Visual Studio in conjunction with Ironspeed. So I suppose that would have to come out too.

Then, to make it consistent, I suppose all my Visual Studio projects would have to come outside the virtual machine.

And then - what happens if I want to go out of town for a week and take my laptop. How do I easily move all this stuff from desktop to laptop?

The Virtual machine becomes useless. All because Ironspeed doesn't like you using their products in a virtual machine.

So one software supplier digs their heals in over technological innovation. Where will this end?

I predict one of two things will happen:

1. Ironspeed will see the error of their ways, repent, and their next version will run inside a virtual machine. Probably with some sort of licensing service that runs on a physical machine to police the licensing policy.

2. As more developers start using virtual machines, another software vendor will release an alternatuve web development utility, that does what Ironspeed does - except the new software will run inside a VM.

People who work in the technology industry can't run away from technological innovation. Or they will end up being people who USED to work in the technology industry. Technology is all about innovation. Anyone who wants to stay in the technology industry needs to embrace innovation, not shun it.

So, here's my message to Alan Fisher and the great guys at Ironspeed: You guys have a fantastic product. I love it. It's brilliant and makes my life easier. It's worth every cent that I paid for it. But if you want me to chose between Ironspeed and my Virtual Environment, then I'll chose the latter. I want my technological life to be easier, not harder.

Please change your mind.

UPDATE December 2007. The folks at Ironspeed have responded to user requests, and removed the restriction on ISD running in a virtual environment. Fantastic decision, guys. A great product just got even better. Thanks for listening to us!

SSL / HTTPS stops working on localhost under IIS 5.1

2007-09-14T14:18:00.000+10:00

I have an ASP.NET web application that uses SSL.

The other day it stopped working on my development machine (Win XP Pro SP2). Whenever I tried to navigate to the SSL page my browser said it couldn't find the page.

I spent hours trying to google an answer to this problem.

The thing that finally fixed it was.... (drum roll)... a reboot.

Now here's the proof that I've taken leave of my senses. My colleague had the same problem a few days ago. I helped him resolve it, and even suggested the reboot solution. It worked for him. But today when this problem happened to me, I forgot all about that episode, and wasted time until I came up with the same solution. Again.

I must be getting old.

Incidentally, if you need an SSL certificate for testing purposes, try Microsofts SelfSSL utility. It creates the certificate and installs it for you.

It's available at https://www.microsoft.com/downloads/details.aspx?familyid=56FC92EE-A71A-4C73-B628-ADE629C89499&displaylang=en or search for "Internet Information Services (IIS) 6.0 Resource Kit Tools".

IMPORTANT UPDATE: Microsoft's SelfSSL utility will cause MSDE to stop working. It tries to install certificates in the SQL Server which makes it impossible to connect to.

BuzzNet to Blogger woes

2007-05-31T09:55:00.000+10:00

There was a cool feature at BuzzNet.com. It let you email a photo to a secret email address and would then create a blog entry at BuzzNet from the email. Really handy when you were on the road, had some nice photos, and wanted to upload them quickly without stuffing around with URL's and HTML image references and crap like that.

What was also nice was the BlogThis! facility that let you convert the new BuzzNet entry into a Blog Entry here at Blogger.

After I upgraded to Blogger's new gmail accounts, I was unable to use the BlogThis! facility at BuzzNet.

I've been stuffing around with this for ages, and every time I tried to get BuzzNet to talk to Blogger I got errors, and it wouldn't retrieve a list of Blogs.

Eventually I gave up in disgust and tried Flickr.Com.

It works! Perfectly! Easily!

I created a new Flickr account, told it that I had a Blogger account, and it directed me to a page at Google which let me authorize Flickr to update my blog.

Now I can email a photo to a Flickr address, and it automatically creates a new Blog entry for me.

Next time I go on a cruise, I'm all set to upload my new photos every day without spending hours trying to figure out all the HTML references.

I am a very happy camper. If anyone else has this problem with Buzznet - forget them - just upgrade to Flickr and make your life easier.

Laptop Runs like a Dog

2007-04-11T15:54:00.000+10:00

My laptop has been running slowly for months. I thought I had problems with the CPU temperature, the CPU itself, spywarre, viruses, global warming, little green men - you name it.

The penny finally dropped. (D'OH!)

My power management settings were set to "Default Power Scheme". So Windows was throttling the CPU to reduce power usage and extend the life of my battery. That's useless to me because my computer is rarely un-plugged.

I changed it to "Minimal Power Management" and WHOOOOSH!!!!! It's running as fast as it used to.

Nice to have decent laptop power again. I've been putting up with crawling speeds for months. If only I'd found this solution earlier!

Outlook 2003 Runs like a Dog

2007-01-25T11:08:00.000+10:00

I've been growing increasingly frustrated with the amount of CPU time consumed by MS-Outlook 2003 on my laptop.

When Autoarchive runs every morning at 9am, the system grinds to a halt. There's no way in Outlook you can change the TIME at which this process runs. So my solution to the problem is to disable Autoarchive, wait till midnight, enable it, and tell it to run every day. That way I won't be around while it's archiving. How stupid that I have to stay up till midnight because MS products don't work properly. Does anyone know any better solutions to this?

The other contributing factor is my archive folders. I have them visible in the folder window that appears on the left hand side of outlook - so I can see "Mailbox - Me", "Personal Folders", "Archives" etc down the left hand side. I thought this might be slowing things down a bit, so I right-clicked on the Archove and Personal Folders, selected "Close", and the folder disappeared from view. After I did this, Outlook seemed to consume less CPU time, so I think I've solved this problem.

One final thing that might be adding to the overall slowness is the fact that my main outlook mail folder connects through a VPN to my exchange server (i.e. its not local to me). I think the combination of VPN and Exchange might be using up a lot of CPU.

Surely there must be something better?

It Works!!!!

2007-01-12T11:43:00.000+10:00

Ben Tatasciore and his team at Fone Zone Strathpine are legends.

I complained to Ben yesterday about my poor experience with Telstra and he solved my problem. Basically the upgrade to a 3G sim card broke my messagebank service, and Ben helped me navigate the labyrinth of Telstra to find an intelligent lifeform that was able to "Re-provision" my phone and get my messagebank working again.

Thanks for the excellent service, Ben.

Special thanks also to Anthony at Telstra who flipped the right switches and made the right incantations to get it all working for me.

As an addendum to my report about MyPhoneExplorer that I mentioned yesterday, another nifty feature is that when it's connected to my computer, and I receive an incoming SMS, it pops the SMS up on my compuer screen. Plus when someone calls on the mobile while its connected to the computer, a popup flashes on the screen to tell me someone is calling, and it tells me who the caller is.

I am a very happy customer now!

It's a Sony :)

2007-01-11T15:18:00.000+10:00

I love my new Sony K800i mobile phone.

I can email, take photos, videos, browse the net, watch Fox-Tel, listen to the radio and use it as an MP3 player. Mine came with a 500mb memory stick, and a nifty little adapter so you can plug the stick into your laptop.

I have two gripes:

GRIPE 1. The softwae that comes with it is useless. This bloatware is almost 50mb to download. It fails to install, with heaps of DLL errors. Gives errors when you uninstall it, blurts out wierd pop-up messages in chinese when I reboot my machine, and renders the phone unusable when connected to the laptop via USB.

SOLUTION 1. A FANTASTIC program called MyPhoneExplorer - it's free, only 2mb in size, installs with no problems, does everything the Sony software pretends to do and more, and is easy to use. It even has a great utility where you can use your computer keyboard to navigate around the phone rather than pressing the small keys on the phone. If you download it and like it, don't forget to send a donation to the author. He accepts paypal.

GRIPE 2. Telstra. It took 18 hours to get my new 3G Sim Card activated. While they were doing that, by messagebank service died. I tried phoning them 4 times, each time on the phone for 30 to 40 minutes. On 3 of those occastions they cut me off after 30 minutes.

SOLUTION 2. Any suggestions? I won't touch Optus with a barge-pole because they're majority owned by the Singapore government who has the nasty habit of executing people by hanging. I don't know anything about Voda, 3 or AAPT. Telstra is sort of like an alcoholic uncle. You don't like him very much, he does nasty things, but you're worried if you swap him for someone else's uncle you might end up with someone even worse.

This is "cool" (well not as hot as it used to be).

2006-12-05T08:15:00.000+10:00

The screen on my LG LW70 laptop is slowly degrading. Every week I get a new vertical line on it as the pixels die.

I've got an extended warranty on it, so I could return it to get a new screen, but I run my life and my business on my laptop, so I'd rather buy a new one than let it out of my sight for more than a few hours.

I noticed that it was pumping out a lot of heat from the heatsink on the left hand side of the unit, and thought that was normal for laptops. But when the next vertical line started flickering on my screen I got desperate and googled "lg lw70 laptop temperature" and discovered a new utility.

Speedfan (http://www.almico.com/speedfan.php) is a clever utility that monitors the temperature of a PC at several different points (HDD, CPU, Video) and lets you configure responses to certain events if the heat gets too high.

To my horror, when I ran it on my laptop, I discovered that it was running at 66 Celsius, which is pretty hot.

I racked my brain trying to figure out a way to reduce the temperature and came up with two ideas:

I put the laptop on a U-shaped metal tray. The U-Shape meant that air could get underneath it, and the metal tray conducted the excessive heat away from the laptop.
I made the windows power schemes the same whether the laptop is running on batteries or not. So the HDD spins down after 5 minutes, and the Laptop tries to conserve as much power (i.e. produce as little heat) as possible.

The results were drastic. The laptop temperature dropped from 66C down to 44C in about 2 hours.

It won't undo the heat damage that's already been done to my screen, but at least the screen won't sustain any more damage.

Now all I have to do is figure out how to live without my laptop for a week so I can get it repaired :)

I'd recommend speedfan for any machine that has a decent bios and allows monitoring of temperatures.

Sharepoint doesn't send out alert emails

2006-09-01T10:52:00.000+10:00

There are a lot of useful articles in the Microsoft Knowledgebase to help you resolve the problem where sharepoint won't send out email alerts. Some of them are really complex.

BUT!!!! Before you spend hours (like I did) trying all the complex solutions to make it work, try the simplest solution first:

Make sure your mail server allows relays from itself. In exchange, go into the SMTP server properties (Start / Programs / Microsoft Exchange / System Manager / Servers / My Server / Protocols / Smtp / Default Server / Access / Relay / "Only the list below" - Granted to 127.0.0.1.

Memes and viruses of the mind

2006-06-21T10:25:00.000+10:00

A while ago I posted my thoughts about "The Virus of Ideas".

Since then I've been lucky enough to discover the work of Richard Dawkins. His 1991 article "Viruses of the Mind" explains the concept of an idea being analogous to a virus that infects the mind.

He says:

Like computer viruses, successful mind viruses will tend to be hard for their victims to detect. If you are the victim of one, the chances are that you won't know it, and may even vigorously deny it. Accepting that a virus might be difficult to detect in your own mind, what tell-tale signs might you look out for? I shall answer by imaging how a medical textbook might describe the typical symptoms of a sufferer (arbitrarily assumed to be male).

It's worth reading his description of those symptoms. Check out his article if you get a chance - especially if you think you might have been infected :)

Easy backup

2005-08-16T11:10:00.000+10:00

I downloaded Image for Windows (IFW) from http://www.terabyteunlimited.com/imagew.html

It lets me backup my entire hard drive to DVD or CD. Plus it makes the DVD or CD bootable. That means if my hard drive ever crashes, I just boot from the DVD, and it will automatically restore everything.

Amazing. Easy to use. Only $US 27.

My only gripes:

1. It doesn't write to DVD-RW so you can't re-use DVD's.
2. Someone stupid like me could accidentally boot from a DVD and wipeout everything on the hard drive.

Both those gripes are solvable - just use cheap DVD-R disks, and (easier still) don't be stupid.

I'll email their tech dept and let you know if they have a solution for the DVD-RW's.

Addendum (17-Aug-05)

IFW can handle DVD+RW disks without any problems. DVD-RW's need to be fully blanked or brand-new before they will work. So I think I'll buy some +RW's and see how I go! The article is here: http://terabyteunlimited.com/kb/article.php?id=215

Crash recovery - a litany of errors

2005-08-11T15:10:00.000+10:00

Here's how NOT to recover from a faulty hard drive.

I turned on my laptop and got an error while booting about a faulty NTLDR.SYS file - or some name like that. The error said to insert the Windows CD and select option "R" to recover.

My Acer laptop didn't come with a Windows CD, it came with a "Recovery CD". So I inserted that CD, booted from it, and the damned thing started formatting my hard drive. Yes there was some vague warnings in broken English about backing up data, but I was expecting to see a Windows message, and got something totally different.

"Ah!!!!" I screamed as I saw what was happening, and turned my machine off in the middle of the format.

Now the disk drive was partially formatted, and had no directory info on it.

So I plugged in my trusty USB drive backup, and went about getting the machine ready to Ghost the backup drive back to the original drive.

Getting a laptop to boot from a CD and run Ghost is an effort in itself and took me about 2 hours to figure out. If you want to try it yourself, get Ghost to burn a bootable floppy that does the same thing, and use something like UBCD to convert the floppy to a CD.

So I ghosted the backup drive back to the laptop, booted the laptop and.... NOTHING. The USB drive was faulty, and the backup drive was unreadable.

"Ah!!!!" I screamed again in a Homer Simpsonesque panic.

I ran Spinrite on the USB drive in a vain attempt to fix it. But the back up drive was faulty (remember, Neil?) and so it just made things worse - and I lost the partition table on the backup drive.

So I threw the USB drive caddy out the window, and connected te Backup drive to a spare IDE port on my desktop computer. Still no joy.

So I tried a thing called "Diskpatch" which is supposed to fix partition tables. It said a few encouraging words, and did absolutely nothing.

Finally, I tried a thing caled "iRecover". It was able to see stuff on the drive. Most of it was scrambled, but I used it to pump as much corrupted data from the drive as I could.

It has been running for about 7 days, and has almost finished pumping everything from the 60GB backup drive. about 75% of the stuff is rubbish. I was able to recover one or two snippets that were some use to me.

Bottom line - I lost about 6 months worth of work - but was able to scrounge a lot of it back from other sources.

I NEVER EVER want to go through this again. It's bad for my health, my marriage and my business. Here's what I will do in future:

1. Backup more regularly to multiple locations.
2. Use something like NTI to create a bootable backup DVD of my drive.
3. Get a new Laptop - the Acer Travelmate is rubbish.
4. Never try to run windows repair on a faulty drive until I've pumped it for all the information I can.
5. Never trust a USB drive. Especially one that runs hot.
6. Backup more regularly to multiple locations.
7. Buy high quality equipment

The other thing with Laptops - don't move them around until you've put the machine in standby mode. If you do, the diskdrive is still spinning, and there's a good chance you'll stuff the drive up.

You will have one of your disks crash on you sometime in the next few years. It's happened to me 4 times in the last 12 months on 2 different machines. Make sure you can recover from it. Do something about it today.

iRecover is available from http://www.diydatarecovery.nl

It works, but it is damned slow.

Loan repayment calculations and high school algebra

2005-03-12T17:37:00.000+10:00

FV = (PMT*(1+RATE*TYPE)*(1-(1+RATE)^NPER)/RATE) - PV*(1+RATE)^NPER

This is the formula for the "Future Value" (FV) of an investment assuming an initial investment (PV), constant repayments (PMT) and a constant interest rate (RATE) over a fixed term of months (NPER). When "TYPE" is zero, loan repayments are made in advance. When "TYPE" is 1, loan repayments are made in arrears.

You can algebraically rearrange the formula to give an expression that calculates PMT.

You can also rearrange the formula to give an expression that calculates PV.

Both of these just require simple high-school algebra.

But you CAN'T rearrange the formula to give an expresion that calculates RATE or NPER.

To work out these figures, you have to use an iterative method where you "plug in" a guess of what you think the rate or period should be, evaulate the result, and adjust your guess accordingly.

If you use some smart iterative methods, you should only have to loop about 5 times. The simplest way is given two guess / result pairs (x1, y1) and (x2, y2), and wanting to find the "x" which will result in "y", your next best guess is to try x = y*(x1-x2)/(y1-y2).

In subsequent iterations, discard the (x,y) pair furthest from the desired result, and repeat the process with the new results.

RAID-1 Upgrade (RTFM!!!)

2005-03-12T17:18:00.000+10:00

My server had 2 x 60gb Seagate IDE drives in a software RAID-1 array.

For those of you who don't know, this means that although I had two 60gb drives in the server, it only looked like I had one, because I'd set it up so that Windows kept a "mirror" of the drive. That meant that if one drive failed, my machine would still work ok because the "mirrored" copy would still be available.

One of the drives recently started showing errors, so I decided to replace it.

Although 60gb drives are still available, I decided to replace the array with two 160GB drives to give me a bit more space.

The big question was, how to replace the drives without taking my server offline for too long?

One alternative would be to break the mirror (remove the faulty drive from the machine) and replace it with the new 160GB drive, then add that 160GB drive to the mirror. Althoug I wasn't 100% certain, I thought that if I did this, the 160GB drive would only use 60GB of the available space, and I'd be wasting most of it. Despite this, the advantage would be that the machine would only be offline just for the time it took to replace the drive and turn it back on again.

Instead of this approach, I decided to add one of the 160gb drives to the machine as a 3rd disk drive. I would then use Norton Ghost to copy the contents of the mirrored volume onto the new drive. The disadvantage of this approach is that Norton Ghost requires the machine to be offline while it runs in DOS mode to copy the entire contents of the drive, ensuring that nothing gets changed inadvertently while copying from one drive to another.

For some reason I cannot fathom, 10 minutes after starting the Ghost, the screen on the server went blank, and the server died. Initially I thought it was just some sort of lowlevel screen saver in the video card (optimistic, aren't I?) so I left the machine for a couple of hours, hoping that ghost would finish.

Eventually, after trying the same process several times, I came to the conclusion that ghosting a mirrored volume just wasn't going to work. I thought perhaps it was because my power supply couldn't cope with 3 drives, tape drive and DVD drive and so disconnected the DVD and tape. This still didn't fix the problem, so all I can suggest is that Ghost doesn't like copying mirrors.

In the end, I read the instructions on the label of the new disk drive, downloaded a utlility from http://www.seagate.com/support called "DiscWizard for Windows" and ran it.

It's great!!! It found my new drive, formatted and partitioned it for me, then asked me if I wanted to replace an existing bootable drive. I said yes, it copied all the files, then gave me a printout telling me what jumpers to change on each of the drives, and whereabouts on the IDE cable to put the new drive. All with friendly illustrations.

AND it did all the copying while the server was still online.

AND (best of all) it worked!

The added bonus is that DiscWizard is free. It comes with all Seagate drives.

So the moral of the story is that I was trying to be too smart. In this situation, if I had just RTFM (read the fine manual) I would have saved myself about 12 hours of frustrating heartache.

Today I've got two 160gb drives in a mirrored array, and feel very relieved that it's all working again. I'll know next time how to swap my disks over with the minimum amount of messing around.

What's in a #Name?

2005-02-19T18:31:00.001+10:00

Sometimes I've seen #Name? on MS-Access reports.

When it appears, the report is impossible to export to excel.

Rather than pull your hair out, check to see if the correct ADO reference is loaded in Tools / References. Usually the problem shows up as a missing reference. Fix the reference and the problem goes away.

The REAL challenge is when you're deploying and MDE or ADE, because the end user can't change tools / references.

In this case, you should make sure that the DLL MSADO15.DLL is registered. On my machine it lives in "C:\program Files\common Files\System\ado".

The command to register this file manually is:
regsvr32 "C:\program Files\common Files\System\ado\msado15.dll"

Republish info from a web site

2005-02-19T18:31:00.000+10:00

It's really easy in .NET to output your own censored / transformed version of another web page.

Here's a code snippet which reads the contents of one web site, does some changes it, and re-publishes it on your own web site.

Make sure strURL has the "http://" at the front of it, and be sure to take acount of the fact that any relative references in the source web will still be relative in the target web.

Dim objRequest As WebRequest = System.Net.HttpWebRequest.Create(strURL)

Dim objResponse As WebResponse = objRequest.GetResponse()

Dim sr As StreamReader = New StreamReader(objResponse.GetResponseStream())

Response.Write(Page, SomeTransformationOf(sr.ReadToEnd()))

What the?

2005-02-19T13:02:00.000+10:00

Tech Musings is a collection of technical thoughts and ideas by Neil