An entry into the industry

I said in my first post that I would discuss how I got into the IT industry in more depth. I will do this below. What I do want to achieve on top of this is to add some helpful, thoughts of wisdom and recommendations for those people who are new or thinking of entering the industry. First of all. If you had asked me 10 years ago what I was going to be doing now, I don’t think even my 10th guess would have been accurate. What I’m trying to say, is that IT wasn’t a set in stone career for me. I wasn’t one of those lucky people who knew what they wanted to do and how they wanted to do it. The reality was for me, that by the end of high school, I still had no idea what the future would hold. I had been lucky enough in my upbringing to experience all sorts. A rural lifestyle, a good exposure to outdoor pursuits, as well as being brought up on a vineyard, so naturally I had a strong interest in viticulture. I had no calling, so to speak of which way I should go. For this reason, after high school, I bailed overseas to the UK to do a gap year.

On this gap year I was actually working in an outdoor education centre and was heavily involved with instructing and training of both children and adults. I loved it. My heart was in it and I really thought that was me, game, set and match. However. strangely enough , one of the men I was working with at the centre, had an interest in IT, and he ran the network and communications for the site. Surprisingly, I found myself interested in what he was dong. Although what he was doing (Windows SBS admin) brings me no joy now, at the time it was pretty cool. I had always done IT stuff at school, and although I enjoyed it I wasn’t an arty person, so I was never really that great at the website dev etc etc. My school did not teach networking. It’s not something that is taught in mainstream (generally). I always did enjoy a bit of code though, and spent many hours at home in my spare time playing with HTML and CSS etc. I never pursued it as I couldn’t think of much worse that trying to do design when it really didn’t come naturally to me. Basically, IT stopped there for me until I saw a different side of it while in the UK.

When I came back to NZ, the first thing I looked at was getting into teaching outdoor education. I also looked at other careers options. All things outdoors. For various reason, niether of these worked out and I ended up working for the family business. At this point, being 19, in Nelson when a majority of my mates were in Christchurch studying awesome things and living the (then) city life up. There wasn’t much that would stop me going to explore. I started looking into things that I could do in Christchurch. Again, I looked at outdoor ed, but I also remembered the interest in IT that I had gained whilst away. This interest was enough for me to inquire into some courses. The more I read, the more I learned, until I was hooked (it didn’t take much!). I originally started at CPIT (Canterbury Institute of Technology) with the intention of doing a degree in electrical engineering. However to get started, I did a certificate in computer technicians. Whilst doing this, I got a bit of a love for the technology I had began to work with, at such a basic level at this point. I was convinced to carry on the course and do a diploma in computer networking. The diploma was a full time course and started off with (amongst other things) the Cisco Academy course, CCNA 1 – which in an introduction to networking. I carried on enjoying this area and went through the entire CCNA curriculum at CPIT. This was of course along side a bunch of other classes. These included a bit of AD, Some Security as well as what was my favourite course – Network Analysers. This course focussed on basic but essential ‘real life’ networking. We worked with WireShark till we knew it inside out (specifically we analysed the hell out of Radius). We did a bunch of cool stuff in this course. I often call on this stuff, even now.

If you are thinking of joining the IT industry. Go for it. However, be careful in how you approach it. I know all too many people who get into the industry without knowing what they are in for. It’s hard work and you have to realise that for most of us in the industry, study is inevitable – probably for all of your career. Technologies are constantly changing and being developed. There are companies that are incredibly innovative and are fast developing technologies to deal with the incredible uprising of technology in the last decade, as well as preparing for the next decade. It’s not one of those industries that you learn for 3 years then that’s you sorted for life. For me, that’s what I love about it. For some, that may be the worst thing in the world. There is however something special about keeping up with the newest and best technology that’s ever been invented for a specific purpose within the industry. That’s always going to be the most amazing thing about the IT industry. What’s an amazing way of doing things today, may in fact be a dead technology tomorrow (well, in a few years realistically). Once you’re in, you’re in and you’ll be addicted. It will take a while to gain a basic understanding. An understanding that you will need to have in order to get on to some of the more advanced, cooler stuff that we work with.

What I want to touch on quickly is how we are best to start and give ourselves the best opportunity for success. What I also want to discuss (very quickly mind) is a couple of the options for introductory certifications. This is all my personal opinion, from which I have gained from my experiences entering the IT industry, are more specifically becoming a Network Engineer at a Large NZ ISP. When first learning basic networking, most courses that I know of and most networking certifications at this level cover a broad variety of topics. They give enough information for an insight, and to gain a pretty good understanding of the purpose of a technology, or more specifically  rqnge of commonly used protocols. They teach us of common topologies, likely situations, and problems that are likely to occur over certain topologies and offer general good practice to avoid and work with such issues.

The two certifications I have had experience with at this level are CCNA (Cisco Certified Network Associate) and JNCIA (Juniper Networks Certified Associate). Both are great entry qualifications for their respective companies. I’m not going to delve too much into these. As far as I’m concerned, they are both great entry level certifications which I would recommend doing. If you’re a CCNA then have a look over the JNCIA material. I certainly found it very interesting moving between the two vendors and I felt that almost straight away after getting into the JNCIA and playing with Junos, an ‘oozing’ of innovation and enhanced functionality. Anyway, I could talk about that topic all day but that’s not what we are here for. A quick bit of advice though, is that you’ll come across several vendors throughout your networking career. Be open to learning the operation of different vendors, as in my experience you never know when it’s going to be useful. Once you’ve had a taste, you’ll probably find you begin to find your niche, or a certain thing that you enjoy. That is one of the benefits of the broadness of those certs – you’ll know pretty quickly what you like doing and what you can’t stand.This is really the deciding factor of the next logical question. Where next? Obviously there’s multiple options. The ones that are most likely to come into your mind are; Routing and switching, or security….. I say this because it’s something that crops up at my workplace. We have a range of brilliant engineers. Some of which focus on the core operations of our network functionality, while others have a security focus. Depending on where you are lucky enough to enter the industry may well influence your decision to this question. My personal belief is to focus on the area which you enjoy the most and run with that till you’re at a level you are happy with. Then at such point I think you can start delving into other disciplines within the industry.

In regards to the next certifications, after completing your first entry level qualification. That’s up to you. Take into consideration the things I have put above, but at the end of the day it’s your decision. Personally, I’m loving the Juniper Service provider Qualification path, and plan to keep attacking this in the form of JNCIP-SP within the next few months. The last thing I want to say is that, as with anything, your success will depend on multiple things. The one thing that in my opinion is an absolute must is the willingness to go out of your way to learn. I know it sounds pathetic and cliché, but I can honestly say that if I had not worked my arse off in the first 3 years of my career (and still now :P) then my development and progression would have been severely hindered. Not because I didn’t have it in me, but because there would have been others who wanted it more. So, don’t let that be an issue. Be the one who wants it the most, be the one who is eager to progress. Back it up with hard work, skill, and of course qualifications. The other thing that I need to say is that, I have found there to be a great community within the industry. I’ve never not been able to find the answer to a question. Some of this is down to the awesome people I work with, but some of this is also down to the contacts you pick up along the way. People in the industry are generally very happy to help. So, with that I will say, never hold back. There is no such thing as a stupid question!

MPLS link utilisation

Growth in an ISP is inevitable in the world we live in. A world where more and more people are venturing into the cloud. While some people see this as a good thing, and the way forward, others strongly disagree. Me, well obviously I work with technology every day, so I have my personal views on a wider view of the industry. But, you will not hear about those today (that’s a whole different discussion 😉 ). Today we talk about how, in an ISP environment we can begin to manage growth on core links. In particular how we can utilize the links we have between core devices to their full potential, but also how we can make these networks smarter, so that they can detect when interfaces are at capacity, and when to start moving traffic on to a different link. Specifically we are going to answer this question with the use of auto-bandwith allocation and RSVP subscription.

Let’s say you have a physical interface of 10Gb. The interface is on a PE (Provider Edge) and connects directly to a P (Provider) router. You run MPLS with RSVP on this interface. You have multiple LSPs set up to other P and PE routers in the network. You have multiple L2 and L3 VPN’S traversing the network, with multiple sites in different VRFs on this box. Let’s quickly have a look at a basic MPLS setup with RSVP, with one LSP set up. (each LSP is uni-directional – always remember this) –

1)adding the mpls family to the desired interfaces, no need to be done on loopback set interface xe-0/0/0 unit 0 family mpls

2) link the interface with the routers MPLS process: – set protocols mpls interface xe-0/0/0.0

3) enable RSVP on desired interfaces – set protocols rsvp interface xe-0/0/0.0

4) configure the label switch path between ingress and egress – set protocols mpls label-switched-path r1-to-r5 to x.x.x.x – no cspf(no Traffic Engineering) – In an advanced MPLS network you would usually use several TE options, but we are not discussing this at this point. – set protocols mpls no-cspf

root@Dave-Lab# show | compare
+  interfaces {xe
+      xe-0/0/0 {
+          unit 0 {
+              family mpls;
+          }
+      }
+  }
+  protocols {
+      rsvp {
+          interface xe-0/0/0.0;
+      }
+      mpls {
+          no-cspf;
+          label-switched-path r1-to-r5 {
+              to;
+          }
+          interface xe-0/0/0.0;
+      }
+  }


By default, the entire 10 gig can be used for RSVP reservations. We can under subscribe this interface using 2 techniques. Why would we want to do this? What’s wrong with using the full capacity of the interface for RSVP reservations? – When we are using auto-bandwidth option, which we can configure to read overall congestion on a link periodically. This is an average, right. So this allows for spikes. We never want our interface to be running at 100%, so if we set it to 80%, then we know we have room for upto 20% of spikes over a half hour period. If it does reach a consistent average of 80% then it will start to move traffic off the link using make before break (adaptive) As this is done on a 30min average, if we don’t set the subscription, then in order for LSPs to be kicked off and moved on to another link (using make before break) it would have to reach an ‘average’ of 100%, which is extremely unlikely.

1) Changing the bandwidth for RSVP (with or without CSPF)
- done by percentage of current bw
- set protocols rsvp interface xe-0/0/0.100 subscription 80%
- By default, this relies on the physical interface speed. Ie, if we have an xe interface, then 80% would be 8Gb.

You can also acheive similar results by adjusting the bandwidth that RSVP believes that the interface has.

2) Done by changing what RSVP believes is the bandwidth
- set protocols rsvp interface xe-0/0/0.100 bandwidth xxx
- the above config changes the amount of bw available for LSP reservation

You can use a combination of the 2 ways, Which I believe is better, as it’s more specific. See below for example. Note that I am adding the ‘auto-bandwidth’ statement to the ‘edit protocols mpls label-switched-path r1-to-r5″ hierarchy. CSPF is going to be required to make use of the TE-information you are putting in here. With CSPF, each box standing up a LSP can see what is happening on the network. Without it, you just follow the IGP. If a link is full, you are just going to fail the LSP if it is on too full a link without CSPF information to know what is actually going to be able to fit it!

You must enable the statistics switch, under the ‘protocols mpls’ hierarchy in order to enable MPLS to collect traffic stats,
about all MPLS sessions. You can chose to save this information in a file which you can name and set a size limit. Below is
an example config that configures MPLS to collect traffic on all LSPs on the box every 10 minutes, and save this information in a file called
mpls_auto-statistics. We then look at the ‘adjust-interval x’ switch under ‘protocols mpls label-switched-path r1-to-r5’ hirachy
which tells us how often to make any necessary changes to LSP reservations. Basically says: Do I need to boot any LSPs off this physical
link in order to meet the configured bandwidth requirements. If I do, then setup the LSP over another link using make before break.
Once that LSP is up, traffic will be moved over to it and the existing path will be torn down.

root@Dave-Lab# show |compare
[edit protocols rsvp interface xe-0/0/0.0]
+     subscription 80;
+     bandwidth 10g;
[edit protocols mpls]
+    statistics {
+        file mpls_auto-statistics size 5m files 5;
+        interval 600;
+        auto-bandwidth;
+    }
[edit protocols mpls label-switched-path r1-to-r5]
+     auto-bandwidth {
+         adjust-interval 1800;
+     }


If you configure a percentage of 0, no new sessions (including those with zero bandwidth requirements) are permitted. It’s important to remember that the use of ‘auto-bandwidth’ goes beyond this, and can be used as a good tool to know what going on, on your core links. for example. When auto-bandwidth is in action, it gives me the current reserved bw (ie what the bandwidth reservation of all LSPs combined on that physical link are), as well as the available bw (what we have up our sleeves). We also get a high water mark, which is nice. The actual function of auto-bandwidth is to, in a basic term, know what the link bw is, how much is being used for RSVP, what the max amount of bw it can use, then if that interface get’s full, shift LSPs off that link until we meet the required average. 80% or less utilisation in our examples.

root@Dave-Lab> show rsvp interface
RSVP interface: 6 active
                  Active Subscr- Static      Available   Reserved    Highwater
Interface   State resv   iption  BW          BW          BW          mark

So, really, what we have here is the basics on auto-bandwidth and using the subscription facto to actually make it worth while using. I’ll post further down the track some more advanced options for this feature. I have recently been working with this at work, so will be interesting to see the results of this work over the next few weeks.

Thanks to @hoffnz (twitter), as I used his blog ( has a lot of awesome information in it, some of which helped write this post.

A New Year, A new purpose.

Focus: I’ve been in a new role at work for about a month now. While I’m still adjusting to the role, I often think of the path taken to get to this point. In particular I think, How is this year going to be different to the last. What did I get out of last year? Where was I this time last year and where was I at the end. What did I achieve and what did I do to get there. Did I learn, or did I flat line? It hits me around about this point, that the day I reflect on a year and have to admit that I flat lined. Well.. that will never happen. It’s not the way I roll and it never will be. It also becomes apparent that if I don’t want to flat line then I have to plan. I have to be aware of my current purpose. My role. The path to where I am, what I did to get there, and the path to where I want to be (well, at least where I want to be in my head at this point. I don’t think anyone can plan everything). In my opinion it’s crucial to know all this stuff. Otherwise, how do you plan for where you want to be or what you want to do.

Expectations: A crucial factor with almost all parts of life. Almost everything we do, there are expectations. More often than not these are expectations you set for yourself. I find that it can be hard to know what others are expecting of you, if you don’t know what to expect of yourself. Know your limits. Know how far you can push yourself. Then, push that out a couple more notches, and you have your personal expectation. It’s surprising what you can achieve if your expectations of yourself are a balance of far reached, realistic and within your skill level. No one ever got anywhere by under selling themselves. If we swing this back to the workplace, in particular IT, which is such a fast growing industry (both technically and the industry as whole). Who has the expectations? Chances are it’s not just yourself. Some are realistic and some not so much. Some are to do with Skill and some are expectations of other things. Often all short of flying pigs. I personally have struggled dealing with these expectations. Hard to say no, is the most common one for me. Everything is urgent to someone, so for me that’s the hard thing. It does however, come back to expectations. If you are aware of your skill level, your workload, etc etc blah blah blah, then it makes it easier to set expectations to others, so in turn their expectations of you are realistic.  It’s one of those things that everyone is different on, and I think it takes experience to know how you work, and how you manage expectations of yourself, expectations of others and the way others set their expectations of you. A tricky but crucial element, in my opinion.

Back to the original point of the post. For me, this year, I have a different purpose. I recognize this, respect it, plan for it and will thrive on it throughout the year, There will be many things that I can’t plan for, but what I can do is plan for those events. Have structure to  everything I do. Work smart, plan, reflect, adjust expectations as I can and most importantly, learn!

An Introduction – what is this?

Well, my first post. What else is there to do but introduce.

My name is Dave Harrey. I’m 24 and work in the IT industry as a Network Engineer for an ISP in Christchurch, NZ. I’ve been working in the industry for 3 years and thoroughly enjoy the technicality of the job as well is the regular challenges that arise. I’m Juniper qualified up to a JNCIS-SP and JNCIS-ENT level, as well as my Cisco CCNP Switch Exam. Studies continue. (do they ever stop…)

I won’t go into too much detail in this post, however I have a few main goals for this blog. I often find that there are a lot of people who keep a blog, or have an online presence of some form that are at the highest end of their career, or been in the industry a long time. While I personally find these writings very interesting and sometimes inspiring, I am also aware that there’s the other end as well – the beginning. I think it’s often nice to look at things from the perspective of people in this situation – ie wanting to get into the industry, or are at the beginning stages of their career , so I’ll do my best to be open minded.

I first became interested in IT in my late teens, after learning some basics I was hooked and became infatuated with the new age of communications and in particular, networking. I’ll share some more specifics of how I got to my current role (and the training involved) in a separate post. I will talk more about this down the line as I think it’s important for people who are new to the industry or who are contemplating entering the industry to have something to read for a bit of guidance etc so I will help out there where I can. I’ll also do some technical postings, as well as bring things up that I am facing on a day to day basis. As always, there will be a fair amount of randomness and things that I just decide are important that day.