One of the things I'm commonly asked for is advice on what and how to learn when someone new enters into the world of network administration, engineering, and management. I was asked this by a good friend of mine just the other day and as I was handing him one of the networking books from my bookshelf I found myself crossing out all of the sections that were no longer relevant and writing in the things that were missing but important in today's world of networking. For certain, the knowledge that one needs to be sucessful in today's networking community is very different than it was 10 or even 5 years ago. As I was discussing this with him it occurred to me that these same statements also apply to the required capabilties of today's network management systems (NMS).
In general, while success for many network professionals and NMSs of the past was based on the breadth of knowledge and capabilities, today's environments require less breadth and more depth. Let's take for instance some of the things that an old-school NMS and us older network engineers can manage but no longer need to:
* Appletalk, IPX, DECNet, Banyan Vines, SNA and most non-IP based protocols - there was a time when knowledge of SNA and IPX traffic was a hot commodity. Network engineers needed to understand how these protocols worked and NMSs needed to be able to monitor networks based upon them. In today's networks, it's highly unlikely that you'll run into any of those...
* ATM, FDDI, and Token Ring - Most of my knoledge on token ring was learned via OJT but I've probably attended 6 months of formalized, classroom training on ATM and FDDI combined and I can't remember the last time that knowing ATM was made up of 53 byte cells impressed anyone...
Non-IOS like network operating systems - I'll probaby get some push back on this one, but back in the day a lot of folks resisted IOS as it was just one vendor's way of doing things. Anybody else remember working on Cabletron gear? Nowadays, if the gear isn't from Cisco it's highly likely that the vendor used IOS as a reference when designing the user interaction with their network operating system and so understanding Cisco IOS is going to be a HUGE help.
I could go on and on but just as important as what "not to learn" is "what to learn". The more you know about the following items the more valuable you're going to be. Here's my top 5 things that every network engineer should have an in-depth understanding of:
Head Geek's Top 5 Things Every Network Engineer Should Know Well
5. The OSI Model. This needs to be so ingrained into your noggin that you don't even think about it. It's just there.
4. Virtualization. This is going to save you a ton of time and it's going to make you more marketable. Start with VMWare and branch out of business demands. Be sure to understand the entire environment from the physical ESX host, through the virtual switch, and including the SAN.
3. Packet analysis and troubleshooting. If you don't have a copy of Wireshark and the SolarWinds Engineer's Toolset installed on your laptop I have to seriously doubt your credibility as a network engineer. Wireshark is completely free and there's even a free version of the Engineer's Toolset. Be sure that you have these tools and that you're familiar with them. If you're on the phone with a tech support rep from Cisco and they ask you to send them a packet capture you should know how to do it, including filtering and exporting into a format that they can read it.
2. WANs - You need to understand how today's WANs work. Most likely they're either point-to-point connections, VPN based, or MPLS based. You need to understand how to monitor and analyze performance of these networks, how to tell if you're getting what you're paying for from your provider, and how to optimize leveraging QoS, WAN accelerators, and traffic filtering.
1. IP - IPv4 for sure and start getting familiar with IPv6. I'm not saying you have to be able to do subnetting in your head but you really need an intimate understanding of how the different IP based protocols work.
Yes, there are other very important items that we could easily add to this list but for me, these are the top 5. Send me your suggestions and we'll make it a top 10 or let me know which things you're keying on when hiring for this talent nowadays.
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