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Archive for May, 2015

The joy of fixing Windows Update

Most of the time, Windows Update does its thing quietly and without problems. Updates are downloaded, installed and maintained without much fuss. The entire Microsoft/Windows Update channel is one of the most bandwidth intensive features on the internet, especially on “Patch Tuesday.” Again, most of the time things just works, but occasionally things do end up breaking.

Last week I was finally able to clean up a PC in the school that has been having WU issues for months now. Unable to work on the machine due to heavy use by the librarian, I was finally able to do so due to her absence last week, to finally tackle the issue head on without being pressured for time or interruptions. The librarian’s PC didn’t have issues before, when suddenly one day I started noticing that it was being flagged with a red cross in the WSUS Management Console. Manually installing the offending updates didn’t solve the problem, so I was left with a mystery to try and fix the PC without just nuking it and starting from scratch. What was more interesting is that it was only a small handful of updates failing, other updates were being installed successfully.

First thing I did was use the built in System File Checker scan, which found problems and fixed those, but didn’t resolve the WU errors. After that, I ran Microsoft’s System Update Readiness checker, which scans your Windows install in order to fix things. It too picked up some errors with missing files, which I replaced. It took a few run-throughs, but eventually the tool no longer indicated that there were any errors. Unfortunately, the WU errors didn’t go away. Next I tried the Windows Update trouble shooting tool from Microsoft’s support pages. The tool took a while to scan the system and found the error code that WU was reporting and also claimed to fix said error. However, trying to install the offending 2 updates still failed.

Turning now to the net, most advice for the 0x8007000D error code indicates that the actual update installation files have become corrupted or damaged on the hard drive. I thought I might have a sick hard drive on hand, so I ran Seagate’s Seatools to check that idea out. Turns out the hard drive is perfectly healthy according to Seatools. Finally, I followed the other piece of advice, which was to stop the Windows Update service, rename the C:\Windows\SoftwareDistribution folder to something else and reboot. After the reboot, Windows builds a new folder. I deleted the old folder, which recovered almost 5GB worth of space. I went back to Windows Update to check, and the same 2 updates were offered as before. I tried them and lo and behold, they downloaded and installed without a hitch. All of a sudden, the PC was back up to date after a good few months of being out of compliance.

It’s always a good feeling to have a computer back in full working order. While nuking it would have probably saved me many hours, the hassle of rebuilding the librarian’s profile and reinstalling the library management software made the time spent curing the machine worth it. Hopefully from now on out, the machine behaves itself and doesn’t develop issues again down the line.

Bandwidth buffet

For any person now in their late 20’s to early 30’s, the sound of a dial up modem should be a familiar, yet fading memory. Connecting to the internet more often than not meant listening to those squawking devices and hoping that the connection was clean and free of noise that would slow the connection down. As time went on, ADSL arrived, 3G arrived, HSDPA arrive, VDSL and now fibre have arrived. Slowly but surely, the trickle of data coming down the pipes has become a raging torrent, at least for those that can afford the higher speed options.

Driven by the laws of supply and demand, websites have evolved to become a lot more feature rich and complex than in years gone by. Images have gone from highly compressed gif and jpeg files into higher resolution jpeg and png files. Internet video, once an incredibly frustrating experience involving downloadable clips and QuickTime, Real or Windows Media Player has largely evolved into slick, easy to use web based players. Of course, video has also crept up from thumbnail size resolutions all the way up to the current 4K. It’s become really simple: the bigger your pipe, the more you are going to drink from the fountain by consuming rich media, online streaming and more. Creating and uploading content is also more viable than ever before, which means symmetrical connections are becoming far more important to the end user than they ever were before.

Take the following picture below, taken from my school’s firewall logs for 1 January – 30 April 2015:

Stats

That’s a total of 970GB of traffic on 1 ADSL line, the speed of which has fluctuated during the course of the year due to stability issues. We have another ADSL line which is only used by a few people, some phones and tablets, but I don’t have usage stats for that line. However, taken all together, our school has definitely used over 1TB of data in 4 months. At this rate, we may end up pushing close to 3TB by the year’s end. Also keep in note that these stats are without any wide scale WiFi available to students. I shudder to think of what the numbers will be once we have WiFi going, or even if we get a faster upload so that things like Dropbox, OneDrive and so on become viable.

Here’s a second interesting picture as well:

Stats2

Of all the web traffic going through the firewall, 82.5% of the traffic was unique or uncacheable due to its dynamic nature. In earlier days, caching statistics were higher since websites were less dynamic and had far more static HTML code, less scripts etc. That being said, the cache did at least manage to serve about 15% of the total web traffic. Every little bit helps when you are on a slow connection.

In the end, it all goes to show that the more bandwidth you have, the more applications and users are going to end up making use of it. Thankfully, bandwidth prices are much lower than they have ever been, though on some connections the speed is throttled to make sure that the end user doesn’t gorge themselves to the detriment of other users.

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