Cisco IOS CLI – tips and shortcuts

I’m currently working my way through freeCodeCamp and one of the projects is to build a technical documentation page. I based mine on Cisco’s IOS CLI. It features helpful tips on understanding and using the IOS command line interface.

While gathering information for the project I stumbled upon an image that was a visual representation of the IOS command hierarchy. The simple high-level schematic diagram provides an excellent overview of that hierarchy. I’ve reproduced a higher quality version of it here.

I also made a table that provides examples of what the command prompt looks like depending on your position in the command hierarchy. And last but not least I’ve produced a table of keyboard shortcuts that includes animated gif examples of each for further clarification.

All of this has been combined in a single page and is accessible here.

CCNA study material overview.

This is a quick overview of all the material that I used to prepare for and pass the CCENT and CCNA Routing and Switching exams.

Below are images of the physical lab that I built using second hand equipment from Ebay and all the necessary cabling and tools needed to operate it.

Top to bottom: 3750, 2621xm, 3550, 2811, 3550 mounted on a 10U server rack.
Top to bottom: 3750, 2621xm, 3550, 2811, 3550 mounted on a 10U server rack.
Top to bottom, left to right. Network repair tool kit, cat cabling, USB to RS232 DB9 convert connected to a rollover console cable. 2 Raspberry Pi's, RJ45 module adapters, roll of cat 6 cable, DCE/DTE DB60 Crossover Cable and extra Rollover console cables.
Left to right: Network repair tool kit, Cat 5 cabling, USB to RS232 DB9 converter connected to a rollover console cable. 2 Raspberry Pi’s, RJ45 module adapters, roll of cat 6 cable, DCE/DTE DB60 Crossover Cable and extra Rollover console cables.

Cost breakdown

Routers
1 x 2811 with WIC-1T, 256mb memory, 64mb CF £35.00
1 x 2621xm 126mb RAM, 32mb flash £15.00
Switches
2 x 3550 24 Port managed switches £49.98
1 x 3750 24 port switch £30.00
Miscellaneous
10-U Server Rack £26
DCE/DTE DB60 Crossover Cable – 3FT £4.99
USB to RS232 DB9 converter £9.99
WIC-1T Serial WAN Interface Card £6.50
512MB (2x256MB) DDR PC-2700 £0.99
256MB Generic compact flash memory £3.99
Rollover console cable serial DB9 to RJ45 £3.40
WIC-1T Serial WAN Interface Card £2.50
Additional set of Rack mount brackets £7.00
15m of CAT 6 cabling £5.49
RJ45 straight module adapters £6.99
19 piece Professional Network repair tool kit £14.99
Total £222.81

 

Books

CCNA Routing and Switching Complete Study Guide – Todd Lammle
CCNA Routing and Switching Official Cert Guide Library – Wendell Odom
CCNA Switching Portable Command Guide – Scott Empson
* all the above is currently accessible from safaribooksonline.com

Video series

Cisco CCENT/CCNA ICND1 100-105 – Jeremy Cioara
Cisco CCNA ICND2 200-105 – Jeremy Cioara
CCNA Routing & Switching v3.0 – Keith Bogart
CCNA Routing and Switching 200-125 Complete Course – Kevin Wallace
Various material by Keith Barker on youtube

Software

GNS3
Packet Tracer
Minicom
Wireshark
Ubuntu
Virtualbox
Arch Linux

Other

Boson (source for practice exams)
Cisco Learning Network
/r/CCNA
/r/networking

My path to the CCNA Routing and Switching certification.

Expectations vs Reality

I went in with the expectation of being able to pass both the ICND1 and ICND2 exams within a few months. The reality is that it took just over 6 months. I spent 217 hours in preparation for ICND1 and 240 hours for the ICND2 before I felt comfortable sitting the exams. Looking at my logs I averaged around 2.5 hours of study per day over that period.

What worked best for me

I used a broad range of material to prepare for these exams. Books, video series, blogs, forums, youtube, virtualised environments and a physical lab. I made a separate post available here that lists everything I used.

Most of my study and preparation was spent using the Official Cert Guide, GNS3 and Wireshark.  Once I was comfortable using the physical lab it didn’t make much sense to continue to use it other than for verification purposes. The reason why is because GNS3 is not only more convenient, you also have way more options at your disposable. You have a large variety of hardware options, hosts, servers, it’s faster and easier to navigate. You can have a significantly larger network, it comes with seamless integrations for 3rd party applications such as Wireshark, terminal emulators, and virtualisation. You can also use it with live equipment. Even though I ended up spending more time in GNS3 and Packet Tracer the experience with real equipment is an invaluable one, it filled a void that anyone without actual hardware experience is going to run into. I also feel that if you’re trying to become a Network Engineer a potential employer is always going to favour the person who has that experience over someone who’s only done it virtually.

The downsides to having a physical lab is that it requires space, it can get quite hot, the fans can be very loud and once it’s all up and running it’ll be consuming quite a bit of power. You’ll also want some hosts and perhaps some servers for testing purposes. I used a collection of old Raspberry Pi’s and Laptops as hosts and servers in my lab.

Are video series worth it?

My thoughts on using video series for learning is that you don’t need them but they are nice to have. They’re not an alternative but a compliment to books. Most of the authors are at a CCIE level so they all offer pearls of wisdom and advice. Of the video series that I used INE was hands down the best of the bunch. Keith Bogart’s CCNA series is very thorough and you’d expect it to be with the tag line of “experts at making you an expert”.

CBT Nuggets is an alternative source with a lot of great content. Jeremy Ciaro’s CCNA series is excellent. His style is fun and engaging and there were multiple times he had me laughing out loud with some of his impromptu jokes. They’ve got a fantastic group of authors over there. I also really enjoyed Keith Barker’s ‘IPv6’ and ‘Definitive guide to GNS3′ series along with Shawn Powers’ ‘Everything Linux’ series. It’s worth checking out Keith’s youtube channel as he has lot of great material available there.

The last video series I used was by Kevin Wallace. It’s not as in-depth as INE’s but I really enjoyed them, Kevin’s visual examples were some of the best I’ve seen and I emulated quite a few of them for my local lab environment. It’s also worth checking out his blog and podcast. Both offer a lot of tips and advice. I’m looking forward to learning more from Kevin as he’s one of the authors for the CCNP R&S official certification guide.

Best bang for your buck

Consider a Safari Books Online subscription. Occasionally they have a sale and for $199 you can get a year’s subscription. Considering the amount of content on there for just the CCNA alone, it’s easily worth that investment. All the books that I used are available on there and they have multiple CCNA related video series there by prominent figures in the industry. Wendell Odom and Kevin Wallace being two of them. CCNA aside they have material on absolutely everything tech related you can imagine. Safari Books Online is owned by O’Reilly Media, need I say more.

Other resources to consider

The subreddit /r/ccna was a place I frequently visited. Check out their wiki and ‘helpful resources’ section, there’s plenty of solid advice and links to free material, including an entire video series. Occasionally you’ll see companies like Boson handing out discount codes on there too. It’s a great place to engage with people who are on the same journey.

Cisco’s community forums are good too with a lot of helpful people on there. Their VIP perspectives section has some great articles and a lot of popular authors also reside there. If you have a question this is one of the best places to ask.

Practice exams. I never intended to use practice exams but being uncertain if I was ready or not it was drew me to them. I decided to use Boson over Cisco, based on feedback and reviewing what both have to offer, Boson was the logical choice and I was happy with my experience. It exposed some big holes in my learning. When I thought I was ready I scored on average 60% on Boson’s practice exams. By the time the exam was due I was scoring 90%+. Boson provide detailed answers and explanations on all of their questions in study mode. Simulation mode closely resembles the real thing, right down to the quirky Cisco simlets. They also offer a No Pass, No Pay guarantee. If you fail, they’ll refund you. I found the experience worthwhile enough that I plan on using them for the CCNP exams.

Regarding the actual exams. Everything you need to know about the whole process is available over on Pearson Vue’s website. They have a tutorial available here  and a demo of what the exam is like here. There really isn’t any unique insight that I can offer. You’re better off checking out the CCNA subreddit as that’s a popular topic of discussion over there.  I failed my first exam with a score that was brutally close to the pass mark, re-booked it for a week later and passed it. That was part of the reason why I invested in a practice exam for the ICND2 which I passed first time. The one bit of advice I would offer is to take your time on the simlet questions. On my first attempt I had finished the exam with about half an hour to spare because of improper time management. Wendell Odom provides a strategy for this in the official cert guide. My advice is to not rush the simlet questions, you can make the time up easily with the multiply choice questions.

What’s next

My next goal is to obtain the CCNP in Routing and Switching and return to the CCNA level to either take the Security or Wireless path. That could possibly change in the future but for now those are on my to do list. Outside of the Cisco/Networking realm I’m currently working my way through freeCodeCamp’s curriculum and I also have the LPIC-1 certification on the periphery.