Saturday 29 June 2013

D-Link's Impressive Powerline

I know that these devices aren't new, but I've never used them before today: D-Link's Powerline network adapters are superb and a great way to extend your network to those hard-to-reach WiFi spots.

Setup time is minimal (around ten minutes with all the plug & sorting and cable untangling!) and connecting your PC to the network gives new meaning to the phrase plug 'n' play. All-in-all I'm very impressed.

Just one word of warning: the RJ45 cables supplied in the starter kit are around 450mm long (around 18") and nowhere near long enough for any practical purposes. Make sure that you've got a couple of spares handy or buy some when you order your starter kit.

Sources & References:

Wednesday 19 June 2013

Fixing Grub

After resurecting my old WinXP drive recently, the GRUB menu appears during the startup routine on my workshop machine. It's probably because two operating systems are detected during the boot sequence but as I never intend to use WinXP on this machine, this behaviour is a little irritating - fortunately, it's easy to fix!

From a terminal (Ctr+Alt+T), open your grub file:

sudo gedit /etc/default/grub

Input your password when prompted and make the following changes:

  1. Un-comment line 2 #GRUB_HIDDEN_TIMEOUT=0
  2. Change line 3 from: GRUB_HIDDEN_TIMEOUT_QUIET=FALSE to read: GRUB_HIDDEN_TIMEOUT_QUIET=TRUE
  3. Amend line 4 to read: GRUB_TIMEOUT=0

The relevant part of the amended file should look similar to this:

GRUB_DEFAULT=0
GRUB_HIDDEN_TIMEOUT=0
GRUB_HIDDEN_TIMEOUT_QUIET=true
GRUB_TIMEOUT=0
GRUB_DISTRIBUTOR=`lsb_release -i -s 2> /dev/null || echo Debian`
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"
GRUB_CMDLINE_LINUX=""

Save and close the file and then update grub:

sudo update-grub

Reboot:

sudo shutdown -r now

Sources: & References:

Thursday 13 June 2013

Back to the Future - Ubuntu & Win98

One of the nice things about starting your own IT support business is meeting fascinating people who have interesting or unusual requirements: recently, I've been helping a customer to install Win98 on modern hardware, not as straightforward as it sounds!

Although rare, it's not unheard of for people to be running legacy systems in the UK: I know of several companies that use Win98 on closed networks to run machinery and many of them are finding it increasingly difficult to maintain the hardware. Nonetheless, developing bespoke software to run on Win7 or Win8 still makes migration to newer equipment financially unappealing when compared to nursing archaic computer equipment.

"OK", I hear you say, "but what's this got to do with Ubuntu?" Well, although I did manage to get Win98 installed and stable on the XP machine, getting it to communicate with peripherals (such as the dot-matrix printer and a floppy drive!) proved beyond me: it just didn't want to play. Clearly, this was of no use to my customer who then started to make plans to import a machine from the US specifically to run a fifteen year old operating system. It's then that we started discussing the option of virtualizing Win98 on an open-source operating system using one of the freely (and free!) available virtualization programs.

Installing Precise on the WinXP box was easy and the processor had no problem driving VirtualBox. Fortunately, my customer was using WinXP SE (by all accounts, much easier to get running on VirtualBox than the previous version), so getting Win98 running was also simple but we still had several issues to resolve.

The first is purely aesthetic: in VirtualBox, Win98 SE only runs in a low resolution mode (800x600 16 Color). We fixed this using a very useful utility called SciTech Display Doctor. This is no longer supported, but you can find a registration code online that allows you to use the utility beyond its trial period.

Secondly, we had to fix the ACPI idle time issue (see here for an explanation) - we did this using a utility called Rain which, ordinarily, is used to keep over-clocked processors operating at peak efficiency.

Getting the printer to work was no more difficult than using a IEEE 1284 usb-centronics converter. This didn't work out of the box and we needed to hunt down some drivers. Contrary to some of the reviews on Amazon, our cable had no driver disk (for 98 or otherwise). However, by effectively converting our printer to a USB device, all we then had to do was install the VirtualBox extension pack to enable USB support in Win98 and install a brilliant (and still supported!) utility called DOSPRN.

This approach also worked for a USB floppy drive (without the need for DOSPRN), but with USB support, we no longer needed the restricted format of floppy disks: usb thumb drives are completely supported in this setup and the larger capacities are infinitely preferable to 1.44MB of storage!

On the customer's WinXP box, this setup worked - just! However, replicating it on my WinVista machine was much more successful. Having a dual core processor with plenty of spare system memory clearly helps! So, we'll build a bespoke system to host this virtualization and make the whole enterprise a little more future proof. Of course, the host operating system will be Ubuntu Precise, saving the customer a few bob on a Windows installation ;).

Sources & References:

Backward Progress - normal.mod not found

Recently I wanted to try out some software from the repository for Ubuntu 12.1(+): that meant upgrading my workshop machine's installation from 12.04LTS. Whilst the upgrade went smoothly enough, I found Quantal to be a little glitchy and I couldn't get LedgerSMB to work, so I abandoned the project.

Given that the workshop machine should be as stable as possible, I decided to revert the OS to Precise: easy, right?

Um.....

No

Slipping the installation disk into the drive and electing to format the partition before (re)installation, resulted in the following error on reboot:

file '/boot/grub/i386-pc/normal.mod' not found

Followed by the grub prompt:

grub rescue >

At first I thought that the install had been corrupted and I tried simply reinstalling the reinstall (if that makes sense), but no joy - the same error appeared on reboot. The good news is that the fix was fairly simple: delete the root partition ("/") and recreate it during the installation process. The bad news is that, if you haven't created a separate home partition (or, if you don't have a full, current backup of your files) everything gets deleted as a result!

Fortunately, I am in the habit of maintaining a separate /home partition, so my directories and documents were quite safe during the restoration of Precise. However, if you haven't segregated your /home and root directories, try using the install DVD as a live disk and copying your files to an external disk or drive before attempting to repartition your disk (or backup your system) before down-grading.

Sources & References: