Restart/reset USB in Ubuntu 12.04 without rebooting

Either my Dell Optiplex 990 computer or my Linux install has an issue: occasionally, when I re-plug a USB device into the system, it’ll cause a fault in the USB module in the kernel and USB goes dark. I’m unsure as to whether this is a hardware or software issue, but I’d simply like to restart my USB subsystem and continue working. When searching the web for ‘restart USB in Linux’ and ‘reload USB kernel module’, you get a plethora of results and none of which will work (seemingly due to how the Ubuntu standard kernel is …

in IT · Mon 25 June 2012

Java HTTP request fails with “javax.net.ssl.SSLPeerUnverifiedException: peer not authenticated”

Searching the above-mentioned stack trace reveals lots and lots of results, unsurprisingly.  Most results are workarounds where you modify the code, but what about if an application (like Jenkins/Hudson CI, in my case) throws this error at you? The reason the error is occurring is because the SSL certificate of the target you’re connecting to isn’t considered valid by your Java instance’s keystore. This may be because the certificate itself is invalid, or, in my case, the CA chain couldn’t be validated (my OS is RHEL (Red Hat) 5.7, with OpenJDK 1.6).  For …

in Linux · Thu 16 February 2012

Configuring pulseaudio-equalizer defaults

I’ve recently been using the Logitech G930 headset with my Ubuntu 11.10 install and I’ve found that the default configuration offers nothing in terms of decent sound (tinny, no bass, etc). Thankfully, I’ve been able to turn to pulseaudio-equalizer for help with turning down the treble and up the bass. However, using pulseaudio-equalizer-gtk wasn’t an entirely satisfying experience as the default volume for my headset kept being set to 100% upon restart. Now, if you recall my previous post on this headset, having the volume for the device set at 100% leads to static being …

in Ubuntu · Fri 16 December 2011

Logitech G930 Headphones audio quality under Ubuntu

So I recently purchased a new set of Logitech G930 headphones and am currently using them with the latest version of Ubuntu, 11.10.  Set up was a breeze - just plug, check your PulseAudio config, and play.  For those of you, like me originally, who were wondering whether the G930 works on Linux, it certain does on Ubuntu.

Now, it wasn’t all peaches and cream because of two things.  Firstly, the audio output with the default configuration was completely lacking any depth and ‘substance’ to the sound being produced.  I’m not an audiophile and I have slight hearing …

in Linux · Mon 24 October 2011

SCP remote files back home using reverse SSH (in 1 command)

My recent work has involved copying files from a remote host, only accessible via a hop, back to my local computer. This has been simple in the past as the remote host has been able to connect to the local computer and SCP files directly, on account of the firewall allowing this. Recently, the firewall against the local computer has been reconfigured for security and direct connection is no longer possible. I could pass my files through a 3rd-party that both the remote and local machines can get to, but let’s say I don’t have one.

What you …

in Linux · Tue 13 September 2011

How to: Updating OCZ Vertex 3 SSD Firmware (on a Dell M1530 laptop)

I’ve just shelled out a good chunk of money in buying an OCZ Vertex 3 240GB solid state drive (SSD) and it’s amazingly quick. So amazingly quick that I thought I may just have fallen into a coma when I had to temporarily switch back to my old mechanical hard drive and boot from it again. And …

in Hardware · Sat 21 May 2011

Plone/Zope: Truncating a Data.fs back to a certain date/time

Okay. So, anyone out here who’s listening — particularly those overly-enthusiastic users — don’t try to recursively wget your Plone site (or other CMS, for that matter) whilst you’re logged in with an account that can make edits. It will lead to a very bad situation where your site administrator and technical team need to step in and fix your mistakes. For the uninitiated, a loose recursive wget (when logged in with some degree of Edit rights) will hit every link that’s on your pages, and I mean in the (X)HTML source. For a Plone site, this …

in Plone · Tue 20 July 2010

Linux: Make time with faketime

So you, like me, have hit a situation where you’ve got a time-sensitive application that won’t run? Maybe you’ve downloaded one of those apps (like a demo) that won’t run after a certain date and time because it’s “expired”. Or else, maybe some other arbitrary time constraint is keeping you from running a Linux (or even Windows) program. On Linux (Ubuntu for me), there’s faketime to the rescue - a very handy tool that does what it says on the box, changes the system time for given command.

After installing faketime by something like:

sudo …

in Linux · Mon 12 July 2010

Installing Python 2.4 on Ubuntu 10.04 Lucid Lynx

Whoops.  No one sent me the memo that Python 2.4 support was being removed entirely from the latest version of Ubuntu, 10.04 Lucid Lynx.  To be fair, I was presented with the message that ‘these outdated packages will be removed’ and in that list was python2.4.  I made the unfortunate assumption that this just mean the package was outdated (which it certainly is) and I’d have the ability to install it again in Lucid.  There were a number of different packages on the list and in order to save time, I let the updater remove them …

in Linux · Tue 04 May 2010

Ubuntu 9.10 install hiccough

Yay, the new version of Ubuntu is out.  With it comes plenty of cool new features (how awesome does the start up and login screen look now?) and also plenty of opportunities for things to break when I’ve become so accustomed to having them working.  At least it’s not Windows though — I think I may just gnaw my own limbs off before I have to get forced to upgrade to Windows 7 for gaming reasons.

But I digress, there was one reasonably small problem with the upgrade that I saw on both of my Ubuntu machines (laptop and …

in IT, Linux · Fri 30 October 2009