Friday, April 28, 2017

Dell Enterprise Open Switches and Open Daylight SDN Controllers - Is the ideal SDN model ready for Prime Time?


Tuesday, April 25, 2017

NBN - How to Avoid a Crap Merchant RSP (A work in progress)

Introduction

Sooo.

You're a Government.
And one day in 1999 you are sitting around going, hmmm, we're rather crap at managing a budget and we need some money.
I know! Let's sell off our telecomms infrastructure (because that never ends badly)!
So you privatise your telecoms and who would have thought - it gets turned into a maximum profit, minimum effort outsourced pile of rubbish.
The solution? Let's build a NEW government telcomms network!
Except instead of controlling the whole lot and making sure it's a good quality service, let's leave the messy, risky stuff like supporting customers and making sure there's enough backhaul bandwidth to any business who wants to play and not hold them to any performance standards at all!
And it shall be known as NBN. 

I know all that sounds a bit harsh, but tell me why I'm wrong :p

My ADSL Experience with Exetel

As a bit of a history lesson, I'll give you some insight into the service I've come from.

I've been using an ISP called Exetel for the better part of 10 years.

Exetel used to be a great ISP (in that you got the performance that you paid for) run by a guy called John Linton who sadly passed away in 2012.

Exetel's concept was that they were an ISP for techies with very little support (with the idea that you should be able to figure things out for yourself) with the added bonus that the provided 1:1 backhaul contention ratios, meaning you got what you paid for.

Here I was in probably 2010 and was using an Optus resold connection through Exetel paying $45 / month for a full performance ADSL2+ connection.

That's right - I was sitting there getting ~20Mbps down. Any time of the day. Any file from any country, transferred at my sync rate.

You could tell Exetel was run by true engineers through their open publishing of MRTG graphs demonstrating the usage of their peer and backhaul links as follows (with some captures of the old login pages shown to demostrate the difference between how they were then and, well, take a look at the site now):









Unfortunately, following Johns passing, profit margins seem to have taken priority over network performance and the things that set Exetel apart such as 1:1 subscription ratios and visibility into network performance have disappeared.


My NBN Experience with Exetel

Woohoo. NBN is coming to my house!

It's 2017 and all this money has been spent by the Government so I must be getting an AWESOME connection that will absolutely fly.


I look at the RSP websites and they're all very glossy, filling me with hope that this is a polished operation.

The woes of yesteryear of different ISPs providing widely varying performance for services such as ADSL are behind us, right?


Well, here I sit on a supposed 25Mbps down / 5 Mbps up plan from Exetel (FTTN VDSL2 - the most common form of NBN delivery).

I just did an Ookla speed test to a Brisbane based server at 8:30pm on Saturday 23/04/17.

To make things a bit more scientific, I ran up SNMP monitoring of my routers WAN interface to capture the overall traffic and make sure something else on my network isn't chomping my bandwidth.

As they say, a picture is worth a thousand words.




Here we have a graph showing the WAN bandwidth. It averages it out so you don't see the speedtest but you get the general idea that the WAN interface isn't flogged.



 

Here's the super crap results of the bandwidth test.
Exetel - hang your head in shame.
Remember - this is LOCAL traffic within AU.




For good measure, just showing the sync rate and actual rate of the VDSL connection.

Let's try an international download:





73.3 KB/sec.
That's 0.58 Mbps for those of you playing at home.



So, just to recap, it's 2017 and I'm now paying $79 / month for an NBN connection which performs at only 10% of the (download) speed my service which cost $45 / month back in 2010.

Rather than read online chatter, I thought I'd take this monster apart and pinpoint where the issue is and what my options are to make my NBN connection perform like it's supposed to.



NBN Design and RSP Responsibilities Overview
When you hear "NBN" it immediately conjures up ideas of a giant Australia wide network all owned and built by the Australian Government.

Unfortunately, the reality is that the Government (NBN Co.) only really a portion of the network, specifically:
  • Purchase of last mile delivery infrastructure from Telstra (copper and HFC).
  • Installation of POI infrastructure
  • Blueprint for how RSPs provide core connectivity for NBN provided customers.
NBN performance pain points in detail - Down the rabbit hole we go!


On-Net and Off-Net POI

Domestic RSP Performance (RSP Peering)

International RSP Performance (RSP Backhaul) 

I did my homework and changed RSPs - now my connection works correctly.


How to Avoid Crap Merchant RSPs

 

RSPs - What they can do to PROVE they're not oversubscribing customers.
 

Thursday, March 30, 2017

NfSen on CentOS 7



Ahhh Netflow (and sFlow for that matter).

That magic service that let's you see what's happening on your routers WAN interface.

For new players, there's a fantastic open source product called NfSen that collects Netflow data and provides a GUI with input box to allow you to bring up flow information as and when required (going back as far as your storage can handle).

Now, like all Open Source products, they can be a bit of a PITA to setup.

I've sat down and followed three different guides to get this working on CentOS 7 and found one that was 99.9% there.

The guide I recommend is over at ProLinuxHub @
http://prolinuxhub.com/building-centos-7-netflows-monitoring-station-with-nfsen-and-nfdump/

Follow that guide to the tee with the following changes and you'll be ready to rock n roll:



Extra Packages
On the line that says:
 yum install perl-Data-Dumperu

Change this to
 yum install perl-Data-Dumper

NfSen.conf Settings File
On the line that says:
 $HTMLDIR = "/var/www/nfsen";

Change this to:
 $HTMLDIR = "/var/www/html/nfsen";


Final note:

If you see the following message when you hit up your NfSen URL @ http://x.x.x.x/nfsen/nfsen.php

 Frontend - Backend version missmatch!

Edit /var/www/html/nfsen/nfsen.php

Comment out the line:
 if ( !array_key_exists('backend_version', $_SESSION ) || $_SESSION['backend_version'] !=  $expected_version ) {

And enter directly below:
 if ( array_key_exists('backend_version', $_SESSION ) && $_SESSION['backend_version'] !=  $expected_version ) {

 Save the file.

Restart NfSen:
 /etc/init.d/nfsen restart