henaredegan.com

OpenAustralia DevLive now available in SUSE Gallery

henare — Fri, 25 Jun 2010 01:07:51 +0000

The good people of SUSE Studio have just released SUSE Gallery, which allows you to share appliances built in SUSE Studio (done with the usual SUSE Studio style I might add – “Enabling Infinite Improbability Drive” is displayed when you enable the new features :) nice!).

OpenAustralia DevLive, the ready-to-run OpenAustralia.org and PlanningAlerts development environment, is built with SUSE Studio and you can now find it published in SUSE Gallery.

This means you can download it directly from SUSE Gallery and more importantly, clone it to customise it or to improve it. I haven’t been giving it much love lately ;( so it’d be great if someone added a few new things to it. There’s a bunch of things that could be done to improve it and some bugs to fix, which should probably be added to the ticket tracker.

Installing the Wireshark network analyser on Ubuntu 10.04

henare — Thu, 24 Jun 2010 01:56:42 +0000

Wireshark is a network protocol analyser, or packet sniffer, available for Ubuntu 10.04 via a simple sudo apt-get install wireshark. However to use it correctly, we need to change some permissions to ensure we’re not running the whole application as root.

The following commands will let the adm group run Wireshark without elevated privileges – the adm group is the group that allows you to read log files, etc., I always add myself to it anyway.

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$ sudo chgrp adm /usr/bin/dumpcap
$ sudo chmod 750 /usr/bin/dumpcap
$ ls -alF /usr/bin/dumpcap
-rwxr-x--- 1 root adm 63520 2010-04-13 01:17 /usr/bin/dumpcap*
$ sudo setcap cap_net_raw,cap_net_admin=eip /usr/bin/dumpcap
$ getcap /usr/bin/dumpcap
/usr/bin/dumpcap = cap_net_admin,cap_net_raw+eip
$

That’s all pretty self explanatory – the setcap command allows that binary to use special capabilities, namely to control NICs (to set promiscuous mode for Wireshark) and capture raw traffic from NICs.

Getting an RSS feed of The Drum articles by a specific author using Yahoo! Pipes

henare — Fri, 11 Jun 2010 04:13:53 +0000

ABC’s The Drum is the ABC’s analysis and opinion site. It has a diverse range of contributors and I’ve found the RSS feed a little too active for my liking.

That said, I love the latest presenter of Media Watch, Jonathan Holmes, and I wanted to read just his articles posted on The Drum. I asked if it was possible to get an RSS feed for specific authors but I didn’t get far so I decided to fire up the ever-useful Yahoo! Pipes to do the job:

You can filter by any Author’s name from The Drum (just copy and paste the name from the by-line) and then select Run Pipe then Get as RSS to add it to your feed reader of choice. If you find this useful or have other suggestions for how this could be used, please don’t hesitate to leave a comment below.

Disable your touchpad in Ubuntu/Gnome

henare — Wed, 09 Jun 2010 00:40:57 +0000

If you’re like me and love your nipple, you might prefer to disable the touchpad on your ThinkPad.

In openSUSE this is a trivial affair of opening up the Gnome mouse preferences and unchecking the Enable Touchpad option. When I went searching for this option in Ubuntu 10.04 I couldn’t find it, so I searched the Ubuntu Software Centre for “touchpad” and installed GSynaptics, which looked very similar to openSUSE’s tool.

GSynaptics disabled the touchpad just fine – until the machine transitioned power state, such as suspend/resume or a reboot. I’ve found that the reliable way of disabling the touchpad in Gnome is to fire up gconf-editor and locate a setting similar to the following and disable it:

List the number of members in all Mailman lists

henare — Fri, 21 May 2010 02:34:48 +0000

Here’s a little bash script to display the name of all lists in your mailman site and the number of subscribers for each list, just run it in the same directory as your mailman binaries (/usr/lib/mailman/bin on Debian):

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#!/bin/bash
LISTS=$((`./list_lists | wc -l` - 1))
LISTS=`./list_lists | tail -n$LISTS | awk '{ print $1 }'`
for i in $LISTS; do
echo $i `./list_members $i | wc -l`
done

Protip: you can also just copy and paste the lines into your terminal so you don’t have to save it as a script.

Add a default page title with HAML in Rails

henare — Tue, 04 May 2010 01:11:29 +0000

In the PlanningAlerts project, we recently added a default page title for those pages we forget to add specific titles to. I added the initial code and Matthew ~~did it properly~~ cleaned it up, here’s the diff:

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diff --git a/app/views/layouts/application.haml b/app/views/layouts/application.haml
index 27d81d9..6b42b26 100644
--- a/app/views/layouts/application.haml
+++ b/app/views/layouts/application.haml
@@ -2,10 +2,7 @@
%html(xml:lang="en" lang="en" xmlns="http://www.w3.org/1999/xhtml")
%head
%meta(content="text/html; charset=utf-8" http-equiv="Content-Type")
- - if @page_title
- %title PlanningAlerts | #{@page_title}
- - else
- %title PlanningAlerts | Email alerts of planning applications near you
+ %title PlanningAlerts | #{@page_title || "Email alerts of planning applications near you"}
- if @rss
%link(rel="alternate" type="application/rss+xml" title="RSS" href=@rss)
= stylesheet_link_tag "memespring", "main", :media => "all"

I thought other people might find this little hack useful for adding default page titles to their HAML templated Ruby on Rails projects.

Subscribing to Apple iCal Server feeds from Mozilla Sunbird

henare — Mon, 12 Apr 2010 04:06:49 +0000

Subscribing to feeds from Apple’s iCal Server with OS X’s iCal may be a relatively straight-forward affair but working out what CalDAV address to use with Mozilla Sunbird is another story completely.

It took me ages to work out where these magic feed addresses were but once you know, it’s trivial. In iCal, just select the calendar you want to subscribe and select File, Get Info:

Enter your server address and port, eg. http://yourserversaddress:8008/, then put the CalDAV URL in the image above into the Sunbird CalDAV subscription wizard and you’re good to go:

OpenAustralia DevLive, now with PlanningAlerts goodness

henare — Fri, 09 Apr 2010 01:22:14 +0000

In preparation for the recent OpenAustralia Hackfest – apps4nsw Edition, Matthew asked me to add the Ruby on Rails port of PlanningAlerts to DevLive so that developers could poke around with what was an experimental codebase (it’s now deployed – woohoo!).

Unfortunately I wasn’t able to attend the hackfest as I was busy jumping out of a plane that weekend but I nonetheless managed to get a new release of DevLive ready that includes a development copy of PlanningAlerts.

I’ve added the relevant details to the DevLive page, where you can also find download links for v0.1.0 of the appliance.

If you’re planning to take a look, I think I should alert you (haw haw!) to the fact that the code is moving at a rapid pace and it might be a good idea to pull an updated copy of the code from Github to make sure you’re seeing the latest-and-greatest code.

If you have any problems with this release or any feature requests, leave them as a comment over on the DevLive page.

Monitor Apache 2.2 with Zenoss on Debian

henare — Fri, 12 Mar 2010 05:32:41 +0000

The packaged Zenoss for Debain will monitor httpd out of the box but does not look for the apache2 process.

To monitor Apache 2.2, you need to add a similar Processes class as httpd has. Navigate to Processes>Apache and then select Add process. Type apache2 as an ID (it’s just a unique identifier) and select OK.

Under the Edit tab, type apache2 for the Name and ^.*\/*apache2 as the RegEx. That should be all you need.

To start monitoring a device, just remodel it manually or wait for a day or so for remodelling to happen on all your devices for Apache 2.2 to start to be monitored.

Java and SSL on FreeBSD

henare — Sat, 27 Feb 2010 23:44:15 +0000

Running Jira on FreeBSD, I wanted to be able to pick up email from a Google Apps account and feed it in as tickets. This is normally a straight-forward process but I was getting these errors in the Jira logs:

1	javax.net.ssl.SSLHandshakeException: sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target

So it seemed like the Gmail SSL certificate for IMAP or POP wasn’t validating. That’s weird as it would be a major problem if it didn’t and they’re certainly not using a self-signed certificate.

I checked the keystore and it appeared empty so it looks like FreeBSD’s Java doesn’t ship with the normal list of CAs. To fix this I did:

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[henare@freebsd ~]$ ls -l /usr.local/diablo-jdk1.6.0/jre/lib/security/cacerts
-rw-r--r-- 1 root wheel 942 Aug 6 2007 /usr/ports/java/jdk16/files/cacerts
[henare@freebsd ~]$ #wow, that file's really small (this directory was in our JAVA_HOME - don't ask me about the usr.local thing)
[henare@freebsd ~]$ #first, backup this file
[henare@freebsd ~]$ sudo cp /usr/local/diablo-jdk1.6.0/jre/lib/security/cacerts{,_backup`date +%Y%m%d`}
[henare@freebsd ~]$ #now, copy over the file from ports
[henare@freebsd ~]$ sudo cp /usr/ports/java/jdk16/files/cacerts /usr.local/diablo-jdk1.6.0/jre/lib/security/cacerts
[henare@freebsd ~]$ ls -l /usr.local/diablo-jdk1.6.0/jre/lib/security/cacerts
-rw-r--r-- 1 root wheel 40624 Aug 6 2007 /usr/ports/java/jdk16/files/cacerts
[henare@freebsd ~]$ #that looks better