Evaluating zsh

I’ve always been a bash user but I’ve recently decided to give zsh a while. It has some pretty useful features such as path expansion and replacement (see this slideshare). And yes, I’m well aware of bash-completion thank you very much.

It also has a nice eco system of expansions including oh-my-zsh with which I’m using plugins for git, composer (php), laravel5, brew, bower, vagrant, node and npm. I went with the agnoster theme and for iTerm2 (my terminal application of choice) I installed the Solarized Dark and Light themes. Both work well with the agnoster theme. I also installed and use the Meslo font.

One issue I did find immediately is things like file type colourisation with ls were not as good as bash. To resolve this, I installed the warhol plugin (as well as brew install zsh-syntax-highlighting grc). Now I find my ls’, ping’s, traceroute’s etc all nicely coloured.

We use Dropbox with work and to keep my work and home office laptops in sync, I moved the configs into Dropbox and symlinked to them:

This all works really well. My bash aliases are fully compatible so I just pull them in at the end of .zshrc (source ~/.bash_aliases). Lastly – to prevent the prompt including my username and hostname on my local laptop, I set the following in .zshrc:

So far, so happy.

Disk Usage on Windows under Windows\Installer – Useful Tools

Windows usage is mostly an occupational hazard for access to tools such as Microsoft Visio, VMware vSphere, proprietary VPN software, XenCenter, etc. We tend to use it on an as-needed basis via Parallels on macOS.

For a virtual machine with very little software, the assigned 60GB drive was full. Windows doesn’t display folder sizes in its File Explorer and so TreeSize Free proved a very useful tool for locating the space hogs.

This led me to a system and hidden directory: \Windows\Installer. It had amassed 30GB or orphaned update files. 50% of my allocated space. To clear this up, PatchCleaner worked a charm.

Good hunting.

Linux (Ubuntu 16.04), PHP and MS SQL

In the many years I’ve been using the traditional LAMP stack, I’ve successfully managed to avoid having anything to do with MS SQL server. Until 2016. This year I’ve had to work quiet a bit with it – administration, backups and, now, scripted queries from Linux with PHP.

I suspect I’m (a) lucky I haven’t had to do this before now; and (b) that Azure seems to have pushed Microsoft into greater Linux based support for MS SQL. The evidence? This open source Mircosoft repository with a MS SQL PHP binary driver for Linux released just a few months ago.

NB: installing the Microsoft PHP driver is different to installing the Microsoft ODBC driver for SQL Server on Linux. These may even be incompatible.

For me, I just took a standard Ubuntu 16.04 install (64bit obviously) with PHP 7.0 and downloaded the latest MS PHP SQL extension (for me, at time of writing, this was 4.0.6. When you untar the Ubuntu16.tar file, copy the .so files to /usr/lib/php/20151012/ and then create a /etc/php/7.0/mods-available/msphpsql.ini file with contents:

Note that the tar also contains two ‘ts’ versions of these files. Trying to use those resulted in errors. Link this for Apache2 / CLI as required. E.g. for PHP CLI:

You can confirm it’s working via:

And, finally, for using it, following the the sample scripts from the repository worked a charm.

A Brief History of IXP Manager

For another INEX project, I was asked to put together a timeline for IXP Manager – an open source application for managing Internet eXchange Points. Reproduced here:

IXP Manager was originally a web portal written in PHP by Nick Hilliard in 2005. It was a basic database frontend that just did fairly simple CRUD (CReate, Update, Delete operations) and allowed our members to log in and view their traffic usage graphs.

Around this was a ton of Perl scripts that sucked that data out of the the database and created configuration files for route collectors, graphing, monitoring, etc.

The major achievement of Nick’s original system was the database design (the schema). The core of that schema is still the core of IXP Manager over 10 years later.

I started in INEX in 2007 and started to expand IXP Manager using what was becoming a more modern web development paradigm – Model/View/Controller with a framework called Zend Framework.

There wasn’t a grand plan here – it was just “as we needed” organic growth over the coming years.

In 2010 we decided what we had was actually pretty good and could be very useful for other IXPs. We got committee approval to open source the software and we released IXP Manager V2 in 2010 under the GPL2 license (GNU Public License v2).

This license essentially means anyone can use the software free of charge but also that they should contribute back improvements that they may make. The idea being that INEX would eventually benefit from other IXPs contributing to the project.

Open sourcing a project doesn’t mean it’ll be successful though! What we didn’t do in 2010 was put infrastructure around it such as: presentations at IXP conferences, mailing lists for user support, decent documentation, etc.

We corrected all that and re-released an updated version called IXP Manager v3 in 2012. This time it took off! We also started collaborating with ISOC (The Internet Society) around this time to help start-up IXPs (mainly eastern Europe and Africa) use IXP Manager.

Some established IXPs also contributed money towards development of missing features – most notably LONAP in the UK – and these new features fed back into INEX.

We’ve worked hard on v3 and it’s developed well since with many new features and improvements. Sometime in late 2016 – maybe even this month – we’ll release v4 which is a major leap forward again and should hopefully attract new users and developers.

INEX is very well regarded in the IXP community as an exchange that is well run and both operates and teaches best practice. All of what we’ve learnt running a good exchange has fed into IXP Manager and it helps those IXPs that use it to implement those same good practices. IXP Manager has helped raise INEX’s reputation even further.

Lately we’ve begun to realise that as a small team we can’t do it all ourselves – the more exchanges that use it, the more requests for help and features we receive and as a result, new developments take a back seat.

To try and improve this we launched a new website in 2016 – http://www.ixpmanager.org/ – and issued a call for sponsorship so we could hire a full time developer. The ‘we’ here by the way is my and Nick’s own company – Island Bridge Networks. We’re doing this on a purely cost recovery basis. I’m delighted to say we’ve just about reached our funding goal with three top line sponsors all contributing about €20k each – ISOC, Netflix and SwissIX. The hiring process has now begun!

I’m also delighted to say that there are 33 exchanges around the world using IXP Manager /that we know of/.

Migrate Helpdesk from Cerberus 5 to Zendesk

After seven years of using Cerberus as our helpdesk system at INEX, we decided it was time to upgrade / move on. Following a fairly exhaustive (and painful!) search, we settled on Zendesk as having the right mix of features:

  • agent collision detection
  • a very nice API with an official PHP client supporting composer
  • a familiar workflow to what we were used to
  • enough configurable settings to make it do what we wanted without having to wade through a kitchen sink of options
  • mobile apps for both iOS and Android

The first hurdle was migrating all the existing tickets from Cerberus to Zendesk. There’s a number of ways we could have gone about this but the Cerberus schema was fairly intuitive and Laraval makes bootstrapping an application with database access really easy. As such, we simply iterated over the tickets in the Cerberus database and imported them into Zendesk (with attachments and by creating organisations and users on the fly).

See the code on GitHub at inex/cerb5-to-zendesk.

Doctrine2 Provider for Laravel 5 with Authentication Support

About a year ago, I released a Doctrine2 provider for Laravel 4. We’ve just updated this as a new package for Laravel 5.  Full details can be seen in the project’s README.md.

This package creates four bindings into Laravel’s IoC:

  • Doctrine\ORM\EntityManagerInterface (which is an instance of Doctrine\ORM\EntityManager), also available via the D2EM facade;
  • Doctrine\Common\Cache\Cache (which is an instance of the appropriate cache provider), also available via the D2Cache facade;
  • Doctrine\ORM\Mapping\ClassMetadataFactory (used in this package by the console generator commands); and
  • the Doctrine2Bridge\Support\Repository helper object which used by the D2R facade to instantiate repositories such as D2R::r( 'User' ).

An example of using the D2Cache and D2EM

It includes support for Laravel’s authentication system by way of a Doctrine2 based user provider with some example classes. Simply put – this allows a Doctrine2 database table storing users’ usernames and passwords to be used as the backend for Laravel 5 authentication.

Full documentation of the authentication with examples can be found here.

Available on Packagist and forkable on GitHub.

Nagios Plugin to Check Extreme Networks Devices

Over at INEX we’ve embarked on a forklift upgrade of the primary peering LAN using Extreme Networks Summit x670’s and x460’s. As usual, we need to monitor these 24/7 and we have just written a new Extreme Networks chassis monitoring script which should work with most Extreme devices.

It will check and generate alerts on the following items:

  • a warning if the device was recently rebooted;
  • a warning / critical if any found temperature sensors are in a non-normal state;
  • a warning / critical if any found fans are in a non-normal state;
  • a warning / critical if any found PSUs are in a non-normal state (or missing);
  • a warning / critical if the 5 sec CPU utilisation is above set thresholds;
  • a warning / critical if the memory utilisation is above set thresholds.

You’ll find the script in this Github repository: barryo/nagios-plugins.

A some verbose output follows: