Archive for Cisco

VMware vSphere NanoLab – Part 4 – Network and Storage Choices

Over the past few posts I have gone into the detail on configuring a high WAF vSphere NanoLab, mainly from the perspective of compute. In my case this consists of two Intel NUC nodes, running  dual core 1.8GHz core i3 processors and 16GB of RAM each. The main question people  have been asking me since I published the series is, what do I use for networking and storage?

Prior to the NanoLab, I have always gone for a vInception type of setup, i.e. everything running inside a single powerful workstation with plenty of RAM. This limits your options a bit, in my case it meant simply using local SSD & SATA storage, presented either as iSCSI from my Windows 2008 R2 server  or a nested FreeNAS 7 VM. For a bit of extra capacity I also had a couple of spare disks in an HP Microserver N36L presented via another FreeNAS 7 VM under ESXi.

The most frustrating thing with running your VMFS storage from a Windows host, is the monthly patching and reboots, meaning you have to take down your entire environment every time. In my case this also includes this blog, which is hosted as  a VM on this environment, so moving forward I wanted to have something a little more secure, flexible and robust, which also adhered to the cost, noise and size requirements you might expect for a NanoLab.

Storage

Speed of storage can make or break you experience and productivity when running a home lab. My requirements for a storage device / NAS were:

  • Minimal size
  • Silent or as near silent as possible
  • Low power consumption
  • Minimum 4 disk slots and ability to do RAID 5 (to minimise disk cost and provide flexibility for later growth)
  • Reasonable price

Optionally:

  • VAAI support
  • Decent warranty (if not a home build)
  • Reasonable component redundancy
  • USB3 support in case I want to add any external drives later for some speedy additional storage / backup

After going back and forth between a home-made solution based on another HP Microserver, or a pre-configured NAS, I decided that the additional features available in the Synology “Plus” line were too good to pass up. These include:

  • VAAI support for Hardware Assisted Locking (ATS), Block Zero, Full Copy, Thin Provisioning
  • iSCSI snapshot and backup
  • Link aggregation support for the dual gigabit NICs
  • 2-3 year warranty depending on the model
  • iSCSI or NFS (VAAI on iSCSI volumes only)

They were also recommended by a number of vExperts such as Jason Nash, Chris Wahl and Julian Wood, which is always a good justification to go for one! 🙂

The 1512+ was very tempting, but I in the end I chose the DS412+ due to its near-silent sub-20db operation (thanks to an external power brick and 2 hot-swap silent cooling fans), low power consumption618_348_backup-plans-synology-ds412 (max 44w under heavy load),  minimal footprint and reduced cost. I was tempted to wait and see if a DS413+ comes out any time soon, but Synology are being cagey and I needed the lab upgrades to be done and dusted in a short period. I already have a DS413j which I use for backups, so I can confirm they are very well built little machines, and the noise level claims are indeed accurate!

 

Into the 412+ I have loaded a pair of 240GB SANDisk Extreme SSDs using SHR (Synology Hybrid Raid). This is effectively just RAID1 mirroring when only two drives are installed but gives me the ability to expand out to RAID5 equivalent as I need more space and the price of SSDs (inevitably) comes down. Eventually the box will have around ~720GB or more of useable SSD storage, more than enough for a decent bunch of lab VMs! Another alternative would be a pair of SSDs for VM boot partitions / config files, and a pair of SATA drives for VM data partitions.

Networking

Although you can easily build a great home lab on a flat network with any old cheap switch, the ability to experiment with more advanced features is highly desirable. My requirements for a managed switch were:

  • Minimal size
  • Passive cooling (for silent operation)
  • Low power consumption
  • Minimum of 8x 1 gigabit ports (or preferably more)
  • Link aggregation
  • QoS
  • Security – VLANs, PVLANs, ACLs, & Layer 3 switching
  • SSH access for command line management

Optionally:

  • I am studying for a few Cisco exams over the next year so a Cisco branded router would be preferential
  • Decent warranty

After a great suggestion from Jasper and reading an article by Vladan I ended up going for the ten port Cisco SG300-10.

SG300-10

This 10-port switch will allow for:

  • 1-2 ports per NUC (for 2-4 NUC boxes)
  • 2 LACP enabled ports for the Synology lab storage
  • 2 ports for my personal data storage server (might replace this with a second mid-range Synology NAS later)
  • 2 uplink ports (In my case for a router and a second wireless access point)

This switch is passively cooled, only uses around 10w power, and as an added bonus Cisco include a limited lifetime warranty! Great if you are going to invest that much in a switch for home!

“As long as the original End User continues to own or use the Product, provided that: fan and power supply warranty is limited to five (5) years. In the event of discontinuance of product manufacture, Cisco warranty support is limited to five (5) years from the announcement of discontinuance.” http://www.cisco.com/en/US/docs/general/warranty/English/LH2DEN__.html

If I had been going for a switch purely on cost I would probably have chosen one of the HP models as these have some great bang for your buck, but I did want to stick to a Cisco branded one. I would also have loved to go for the PoE model so I could plug in a VoiP phone later, but the cost for the SG300-10P / MP was at least 50% more, and power consumption would be higher, even when idle.

WAF

The entire NanoLab setup above of 2 NUC boxes, DS412+ and SG300-10 in total take up about the same volume of space as a large shoe box, are virtually silent, and combine for an idle power level of 50-60 watts, and under 100 watts even under load. That’s less than a couple of halogen light bulbs!

In my next post I will go through the process of configuring the network and storage, including link aggregation and suggested VLAN configuration.

Earlier parts of this article may be found here:
NanoLab – Running VMware vSphere on Intel NUC – Part 1
NanoLab – Running VMware vSphere on Intel NUC – Part 2
NanoLab – Running VMware vSphere on Intel NUC – Part 3

Cisco ICND1 640-822 Exam Review and Study Guide

I am embarrassed to say that I am a (seasoned?) IT professional who has never quite found the time to get down and dirty with Cisco networking. As I am about to start a new role as a Solution Architect for a managed service company (who are big into their Cisco gear, MPLS etc), I thought now would be the time to bone up on my 1s and 0s and certify in the Cisco space!

I can imagine that for someone new to IT, the CCENT / CCNA would perhaps be quite daunting, but even having worked with MS, VMware and storage environments for the past 9 years, I discovered that I still had plenty to learn (and in a geeky way, quite enjoyably so!). I did add to my burden by simultaneously going through interviews, completing handovers at my old job, and generally being ridiculously busy whilst trying to find the time to study for this, but even with all that on the go I passed the first exam (640-822) less than 6 weeks from beginning to study the subject. Based on this I would suggest that anyone dedicated to complete the CCENT could comfortably learn the content in full, pass it in 4 weeks of part-time personal study (in my case a couple of hours a night on the nights I had time to work).

I would also say at this point that for those people considering whether to do the ICND1/2 (2 exam) route, or the single CCNA exam, I don’t really know why virtually anyone would consider the latter? The combined exam costs twice as much as the single exam (give or take £2-3), and splitting the exam gives you an initial qualification (CCENT) and an easier ride. Unless you are so time poor that you can only afford enough time to do a single exam (saving you a whole 2 hours of your life), why not take the pressure off yourself and split it? Also if you did happen to mess it up, then you’ve only lost £100, not £200!

The exam itself was not too bad. One question I came across seemed to be bugged, (the responses in the sim to certain commands were conflicting), but other than that it was perfectly reasonable. Bear in mind that the pass mark for Cisco exams is considerably higher than MS / VMware ones, so if you are used to these, ensure you adjust your expectations accordingly. It is also slightly disconcerting not to be able to go back to a previous question; not that I regularly use this feature in other exams, but its always nice to know it’s there if you need it!

In terms of the actual resources I used to study for the exam, they were numerically limited in comparison to those I may use for a VMware or an MS exam, (and more expensive as I generally stick to free resources!), but I felt that to gain the knowledge in the quickest time, it was worth a the meagre financial investment I made (~£45 for training materials, ~£45 for my lab, plus the exam cost – normally covered by my employer, but I was working out my notice period at the time, so even attempting to claim for exams whilst walking out the door isn’t exactly ethical and might get me a slap from my old boss!).

Being a relatively old certification, there is obviously a wealth of different resources out there on the net, but the ones I chose to use are as follows:

  • CCNA Bootcamp by Chris Bryant – $44 (voucher code BULLDOG)
    I’ll say off the bat this is a simply great resource, taught in Chris’ inimitable laid back, easy style. Hey not only teaches you how to pass the exam, but gives plenty of real world advice and anicdotes too. He is also more than happy to answer any questions and does so promptly via twitter, email, Udemy etc. 90% of my learning came from these videos, along with the brilliant binary / subnetting practice questions provided as part of the accompanying ebook.I found that the best way to use the videos was to watch them whilst taking copious notes, then practicing every command and activity discussed using my GNS3 lab. The more you practice this, the better it will stick. I enjoy Chris’ style and have such confidence in his teaching, I have already pre-purchased his CCNA:Security and CCNP courses on Udemy, for which I am hoping to squeeze some time in next year.
  • CCNA 640-802 Official Cert Library, Updated (3rd Edition) by Wendell Odom – ~£15 (Kindle Edition)
    In my case I used this book to supplement / consolidate my video learning, and read the book after completing the video course. It is very well written, and any subjects not fully explained in Chris Bryant’s course are covered in detail here. There are also useful tests at the start of each section to help you guage your progress.You also have the option of buying the same book split into the two exams (ICND1 and ICND2) but the cost of the combined publication works out at half of that of buying the seperately, so why would you?One thing I always mention when it comes to tech books, is that unless you have a need to fill the shelves of your home office with dead trees, I would always recommend opting for the ebook version over the hard/softback. There are several reasons for this, but the two biggest are that the ebook is cheaper (we all like saving money, right?), and what is the point in killing a few trees for a book you will probably only read once or twice, and will be out of date within a couple of years anyway? Add to that the portability of ebooks for later reference and you have a compelling argument… the only draw back is putting money in the pocket of a company who is not particularly great at paying taxes, but other vendors are available!
  • Cisco Binary Game
    Not only is this great geeky fun, but it will hone your brain to very quickly do binary maths without the use of big tables etc, saving valuable time in your exams, and in your actual job. Chris Bryant does a great job in his course of teaching you the simplest and “correct” way of doing binary. Once you have this down and practiced with the binary game, you will easily be able to do binary conversions and subnetting etc in your head (especially when you start to see the patterns used to create subnets etc).
  • GNS3 – Graphical Network Simulator
    For me, this is an absolutely MUST HAVE resource, both for your studying, but also in your day job, where you can safely test any new configurations or commands to ensure you dont break your production environment! In essence it is a Cisco (other vendors are available) simulator, which allows you to build virtual networks using actual Cisco IOS images, and mess with them to your heart’s content. CBT nuggets kindly did a free intro video to GNS3 (link below).Getting hold of the IOS images is also very easy. I would simply say google is your friend (especially when searching for exact IOS image names). To understand how the IOS naming works, see this great little article.Once you have your lab up and running, all I can say is practice, practice, practice! Throughout every video session I had my lab running in parallel, and implemented each command several times on several machines, to really ingrain the commands and knowledge.

    The only drawback of GNS3 is its inability to simulate / emulate the ASICs in Cisco switches. For this they simply give you a fake switch you config from the GUI. If you want to be able to practice switch configuration to a greater level, I recommend getting your hands on a cheap second hand switch. I bought a 24-port Catalyst 2950 switch for just £30 on ebay, and a rollover cable and USB adapter for about £5. This gave me the ability to practice switchport and VLAN commands, have a physical play with the kit, and even link my physical switch into my GNS3 environment using the NIC on my GNS3 host machine! The only drawback is that it’s very loud, so I try to minimise the use of it in my home office! I can imagine the WAF (wife acceptance factor) of a full blown lab would not be great, an even better reason for using GNS3 wherever possible!

  • Intro to GNS3 by CBT Nuggetsfree!
    Great little one hour course showing you how to setup a basic GNS3 environment. They also have a much longer course which you can pay $5 for a month access, but it isn’t necessary for a simple setup.
  • Official Cisco ICND1 Study Resourcesfree! (mostly)
    There are plenty of free videos, pdfs, presentations and even whole lab sims available on the ICND1 page. I would suggest you go through all of them.
  • Cisco Official ICND1 Practice Questions
    Make sure you are able to complete all of these successfully before attempting the actual exam.

In closing, I think the key thing to remember when learning Cisco is lab, lab and more lab… GNS3 is a great resource and more than sufficient for your CCENT (and I would hazard your CCNA) studies. If you have the budget to buy a cheap switch as well (e.g. a 2950) then all the better.

Next steps: New job, Xmas, then CCNA in Jan.

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