Category: Work

INEX’s Shiny New Route Servers

Copy of an article I wrote on INEX’s own blog for longevity – original published here on April 10 2019.

In this article, we talk about the new route servers that we deployed across all three peering platforms at INEX during February 2019 and, particularly, RPKI support.

Most route server instances at internet exchanges (IXPs) perform prefix filtering based on route/route6 objects published by internet routing registries (IRRDBs). INEX members would be used to creating these through RIPE’s database. However there are many other registries and the data quality of some of these IRRDB objects is often poor, with problems relating to missing, stale and incorrectly duplicated information.

A typical IRRDB entry would resemble the following:

route:          192.0.2.0/24
descr:          Example IPv4 route object
origin:         AS65500
created:        2004-12-06T11:43:57Z
last-modified:  2016-11-16T22:19:51Z
source:         SOME-IRRDB

RPKI

RPKI is a public key infrastructure framework designed to secure the internet’s routing infrastructure in a way that replaces IRRs with a database where trust is assigned by the resource holder. The equivalent of a route object in RPKI is called a ROA (Route Origin Authorisation). It is a cryptographically secure triplet of information which represents a route, the AS that originates it and the maximum prefix length that may be advertised. An example of an IPv4 and an IPv6 ROA would be:

( Origin AS,  Prefix,         Max Length )
( AS65500,    2001:db8::/32,  /48        )
( AS65501,    192.0.2.0/24,   /24        )

ROAs are typically created through your own RIR (so, RIPE for most INEX members). These RIRs are called trust anchors in RPKI. RIPE have created an extremely easy wizard for creating ROAs through the LIR Portal.

To implement RPKI in a router, the router needs to build and maintain a table of verified ROAs from the five RIRs/trust anchors. The easiest way of doing this is to use a local cache server which pulls and validates the ROAs from the trust anchors and uses a new protocol called RPKI-RTR to feed that information to routers. Currently there are three validators: RIPE’s RPKI Validator v3; Routinator 3000 from NLnetLabs; and Cloudflare’s GoRTR. INEX currently uses the former two.

RPKI validation of a route against the table of ROAs yields one of three possible results:

  • VALID: a ROA exists for the route and both the prefix length is within the allowed range and the origin ASN matches.
  • INVALID: a ROA exists for the route but either (or both) the prefix length is outside the allowed range and/or the origin ASN is different.
  • UNKNOWN: no ROA exists for the route.

UNKNOWN is a common response as the database has only a fraction of the prefix coverage as IRR databases do. We are now in a multi-year transition from IRR to RPKI route validation while ROAs are created.

Bird V2

As well as RPKI support, we have also upgrading all route servers to Bird v2.

This is a significant rewrite to Bird which, for v1, maintained separate code and daemons for IPv4 and IPv6. Bird v2 merges these code bases and also introduces support for new SAFIs such as l3vpns / mpls.

Overall, the configuration changes required were minimal and INEX continues to run separate daemons of Bird v2 for IPv4 and IPv6 daemons. Route servers are CPU intensive and separate daemons allows for maximum stability, keeps the configuration clean and fits into the existing deployment processes we have built up with IXP Manager.

Route Server Filtering Flow

Our work on the new route servers will be released to the community as part of IXP Manager v5 shortly. The new filtering flow is enumerated below. One of the key new features is that if any route fails a step, we use internal large community tagging to indicate this and the specific reason to our members through the IXP Manager looking glass (more on that later).

  1. Filter small prefixes (>/24 for IPv4, >/48 for IPv6).
  2. Filter martian / bogon ranges.
  3. Sanity check to ensure the AS path has at least one ASN and no more than 64.
  4. Sanity check to ensure the peer ASN is the same as first ASN in the prefix’s AS path.
  5. Prevent next-hop hijacking (where a member advertises a route but puts the next hop as another member’s router rather than their own). We do allow same-AS’s to specify their other router(s).
  6. Filter known transit networks.
  7. Ensure that the origin AS is in set of ASNs from member’s AS-SET. See below for some additional detail on this.
  8. RPKI validation. If it is RPKI VALID, accept the route. If it is RPKI INVALID then filter it.
  9. If the route is RPKI UNKNOWN, revert to standard IRRDB filtering.

Regarding step 7 above, an AS-SET is another type of IRRDB database entry where a network which also acts as a transit provider for other networks can enumerate the AS numbers of those downstream networks. This is something RPKI does not yet support but it is being worked on – see AS-Cones.

Lastly we have enhanced the BGP large community support to allow our members request as-path prepends on announcements to specific members over the route servers. For these and more supported communities, see the INEX route server page here.

Bird’s Eye and the Looking Glass

As well as IXP Manager, INEX has also written and open sourced a secure micro service for querying Bird daemons called Bird’s Eye. IXP Manager uses this to provide a web-based looking glass into our route collectors and servers. We have recently released v1.2.1 of Bird’s Eye which adds support for Bird v2.

We have greatly enhanced IXP Manager’s looking glass to support both Bird v2 and the large communities we use to tag filtered reasons. You can explore any of INEX’s route servers to see this yourself – for example this is route server #1 for IPv4 on INEX LAN1. When members log into IXP Manager they will also find a new Filtered Prefixes tool which will summarise any filtered routes across all 12 of INEX’s route server instances.

More Information

We have spoken about this at a number of conferences recently:

UI Tests with Laravel Dusk for IXP Manager

We use standard PHPUnit tests for IXP Manager for some mission critical aspects. These take data from a test database filled with known sample data (representing a range of different member configurations). The tests then use this information to generate configurations and compare these against known-good configurations.

This way, we know that for a given set of data, we will get a predictable output so long as we haven’t accidentally broken anything in development.

But, as an end user, how do you know that what you stick in a web-based form gets put into the database correctly? And conversely, how do you know that form represents the database data correctly when editing?

This is an issue we ran into recently around some checkbox logic and a dropdown showing the wrong selected element. These issues are every bit as dangerous to mission critical elements as the output tests we do with PHPUnit.

To test the frontend, we turn to Laravel Dusk – an expressive, easy-to-use browser automation and testing API. What this actually means is that we can right code like this:

$this->browse( function( $browser ) use ( $user ) {
    $browser->visit('/login')
        ->type( 'username', $user->email )
        ->type( 'password', 'secret' )
        ->press('Login')
        ->assertPathIs('/home')
        ->assertSee( 'Welcome to IXP Manager ' . $user->name );

We have now added Dusk tests for UI elements that involve adding, editing and deleting all aspects of a member interface and all aspects of adding, editing and delete a router object. Here’s an example of the latter:

Laravel Dusk - Animated Gif Example

Doctrine2 with GROUP_CONCAT and non-related JOIN

Doctrine2 ORM is a fantastic and powerful object relational mapper (ORM) for PHP. We use it for IXP Manager to great effect and we only support MySQL so our hands are not tied to pure Doctrine2 DQL supported functions. We also use the excellent Laravel Doctrine project with the Berberlei extensions.

Sometimes time is against you as a developer and the documentation (and StackOverflow!) lacks the obvious solutions you need and you end up solving what could be a single elegant query very inefficiently in code with iterative database queries. Yuck. 

I spent a bit of time last night trying to unravel one very bad example of this where the solution would require DQL that could:

  1. group / concatenate multiple column results from a one-to-many relationship;
  2. join a table without a relationship;
  3. ensure the joining of the table without the relationship would not exclude results where the joint table had no matches;
  4. provide a default value for (3).

Each of these was solved as follows:

  1. via MySQL’s GROUP_CONCAT() aggregator. The specific example here is that when a MAC address associated with a virtual interface can be visible in multiple switch ports. We want to present the switch ports to the user and GROUP_CONCAT() allows us to aggregate these as a comma separated concatenated string (e.g. "Ethernet1,Ethernet8,Ethernet9").
  2. Normally with Doctrine2, all relationships would be well-defined with foreign keys. This is not always practical and sometimes we need to join tables on the result of some equality test. We can do this using a DQL construct such as: JOIN Entities\OUI o WITH SUBSTRING( m.mac, 1, 6 ) = o.oui.
  3. This is as simple as ensuring you LEFT JOIN.
  4. The COALESCE() function is used for this: COALESCE( o.organisation, 'Unknown' ) AS organisation.

We have not yet pushed the updated code into IXP Manager mainline but the above referenced function / code is not replaced with the DQL query:

SELECT m.mac AS mac, vi.id AS viid, m.id AS id, 
    m.firstseen AS firstseen, m.lastseen AS lastseen,  
    c.id AS customerid, c.abbreviatedName AS customer,
    s.name AS switchname, 
    GROUP_CONCAT( sp.name ) AS switchport, 
    GROUP_CONCAT( DISTINCT ipv4.address ) AS ip4, 
    GROUP_CONCAT( DISTINCT ipv6.address ) AS ip6,
    COALESCE( o.organisation, 'Unknown' ) AS organisation

FROM Entities\\MACAddress m
    JOIN m.VirtualInterface vi
    JOIN vi.VlanInterfaces vli
    LEFT JOIN vli.IPv4Address ipv4
    LEFT JOIN vli.IPv6Address ipv6
    JOIN vi.Customer c
    LEFT JOIN vi.PhysicalInterfaces pi
    LEFT JOIN pi.SwitchPort sp
    LEFT JOIN sp.Switcher s
    LEFT JOIN Entities\\OUI o WITH SUBSTRING( m.mac, 1, 6 ) = o.oui

GROUP BY m.mac, vi.id, m.id, m.firstseen, m.lastseen, 
    c.id, c.abbreviatedName, s.name, o.organisation

ORDER BY c.abbreviatedName ASC

 

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:

cd ~
mv .oh-my-zsh Dropbox/ 
mv .zshrc Dropbox
ln -s Dropbox/.og-my-zsh
ln -s Dropbox/.zshrc

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:

export DEFAULT_USER=barryo

So far, so happy.

PhpStorm and Xdebug – macOS / Homebrew

After many years of Sublime Text and, latterly, Atom, I’ve decided to give an integrated IDE another look – this time PhpStorm. I’ve always dropped them in the past as they tended to crash (hello Zend Studio) and were slow as hell (hello again Zend Studio). But so far so good – I’m only a couple days into an evaluation license but it’s fast (admittedly I have fast laptops – Intel i7’s with four cores, PCI SSD and 16GB RAM) and it’s yet to crash.

One of the key advantages of IDE’s is integrated debugging. This was ridiculously easy with PhpStorm. I use Homebrew for PHP:

$ brew ls --full-name
 homebrew/completions/composer-completion
 homebrew/php/composer
 homebrew/php/php71
 homebrew/php/php71-intl
 homebrew/php/php71-mcrypt
 homebrew/php/php71-xdebug

I’ve then configured xdebug as follows:

$ cat /usr/local/etc/php/7.1/conf.d/ext-xdebug.ini
[xdebug]
zend_extension="/usr/local/opt/php71-xdebug/xdebug.so"
xdebug.remote_enable=1
xdebug.remote_host=localhost
xdebug.remote_port=9001
xdebug.remote_autostart=1
xdebug.idekey=PHPSTORM

If you’re not using Laravel’s Valet for local development then you should check it out immediately: https://laravel.com/docs/5.3/valet. If you are using it, issue a valet restart.

Port 9001 was chosen above as Valet tends to use 9000 also. We now need to reconfigure PhpStorm to list on this port. Open preferences and type xdebug into the search box. Then find Languages & Frameworks -> PHP -> Debug on the left hand navigation pane and change the port to 9001.

That’s pretty much it for PhpStorm. They really mean zero-configuration debugging. When editing a project in the IDE, there’s a Start Listening for PHP Debug Connections toggle icon in the top left – it looks like a phone. Just turn it on.

The last thing we need to do is have an easy way to enable Xdebug when we want it when testing our applications in the browser. Chrome has a very useful plugin for this: Xdebug-helper. Just install it and edit its options and change the IDE form Eclipse to PhpStorm. You can now use this to start a debug session from within Chrome to your listening PhpStorm IDE.

Oh, just found this useful resource also covering similar topics with a CGI/CLI xdebug split.

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:

extension=php_pdo_sqlsrv_7_nts.so
extension=php_sqlsrv_7_nts.so

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:

cd /etc/php/7.0/cli/conf.d/
ln -s ../../mods-available/msphpsql.ini 20-msphpsql.ini

You can confirm it’s working via:

$ php -i | grep sqlsrv
Registered PHP Streams => https, ftps, compress.zlib, php, file, glob, data, http, ftp, sqlsrv, phar
PDO drivers => sqlsrv
pdo_sqlsrv
pdo_sqlsrv support => enabled
pdo_sqlsrv.client_buffer_max_kb_size => 10240 => 10240
pdo_sqlsrv.log_severity => 0 => 0
sqlsrv
sqlsrv support => enabled
sqlsrv.ClientBufferMaxKBSize => 10240 => 10240
sqlsrv.LogSeverity => 0 => 0
sqlsrv.LogSubsystems => 0 => 0
sqlsrv.WarningsReturnAsErrors => On => On

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/.

Personal Profile for INEX

I was asked to write a personal profile for INEX in <= 300 words. Reproduced here.

If you want to confuse Barry, ask him where he’s from: born in Cork, spent his formative years in Galway and married into Dublin. He got a honours degree in Maths, his first love, from NUI, Galway in 2001 and went on to do four years research in information theory in UCD’s Computer Science department.

In 2005 he took a job with imag!ne to help build their ADSL broadband service from scratch to a position where it supported tens of thousands of subscribers. Barry branched out on his own in 2007 when he formed his own consultancy business, Open Solutions, which continued working with imag!ne as well as building up a portfolio of network, VoIP and web application development customers.

It was 2008 when Nick Hilliard, INEX’s CTO, approached Barry to provide a couple days operational support to INEX. Little did Barry realise what a huge part of his life INEX would become – both here in Ireland supporting INEX’s infrastructure and membership but also as part of the larger European and international IXP community.

Barry is the lead developer of IXP Manager (http://www.ixpmanager.org/) – a full stack management system for IXPs which includes an administration and customer portal; provides end to end provisioning; and both teaches and implements best practice. INEX is very proud to say that this project is now in use at over 33 IXPs and has grown legs of its own with the wider community sponsoring a full-time developer.

INEX has always been happy to help other IXPs and, through our relationship with the Internet Society (ISOC), RIPE and Euro-IX, Barry has travelled to countries with a less developed internet infrastructure to advise on best practice, has delivered a number of IXP Manager workshops and contributes to policy development.

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.