IoT Edge and Fog Computing

December 5, 2018 at 7:52 pm

In my CBT Nuggets course – Cisco CCIE Evolving Technologies – we tackle IoT in some decent depth as required of us by Cisco Systems. In this post, I wanted to warm you up for some of that by introducing you to two terms – Fog and Edge Computing.

Fog Computing

These days, all we seem to hear about is cloud computing. And cloud computing certainly plays into IoT, as we’ll discuss. But there’s also edge and fog computing that is quite popular when it comes to the Internet of Things.

Fog Computing

Let’s actually start with fog computing. You’re going to note that both fog and edge computing refer to having processing taking place that is much closer to the actual devices than the cloud. So think about the cloud, public or private. It’s kind of way up there in the stack.

So we might have all of these IoT devices running at a local location. And we want computing to take place closer to them than that faraway cloud. So fog computing is an example of this. And where the processing takes place with fog computing is in the network devices, such as gateways and routers and switches that make up the network.

If we can do some of the processing there, closer to the actual devices– thus, the concept of fog, which is closer to the ground instead of a full-blown cloud– then this is going to do wonders for the IoT implementation. Typically, notice that we’re processing or storing information for the higher levels and those higher levels might actually exist in the cloud. We often do this in a hierarchical type format.

An example I want to give you is temperature monitoring. So let’s say we have these IoT devices that are monitoring temperatures.
 
If we can have intelligence in our network devices and do some fog computing, one of the things that we might have those devices do is see, inside the data, if there’s actually been any temperature change and, if there hasn’t been a temperature change, to stop the flow right there. Otherwise, the device can alert the cloud, and then have the cloud trigger some type of temperature alarm.
 So in this case, it’s reducing the amount of bandwidth we consume, and even reducing processing that we might need to do somewhere else in the stack, based on the fact that there’s been no temperature change.

Edge Computing

Edge computing takes the computing horsepower or the processing horsepower and it moves it even closer to the smart things by actually building the intelligence into the smart things themselves. We sometimes refer to this as mist computing because it’s even closer to the actual devices than fog computing. Typically, it’s intelligence built into those smart devices.

Notice that we could structure this in a very hierarchical fashion. If it’s time-sensitive information, we should be analyzing it as close to the source as possible. We could then use our fog nodes, things like gateways and network devices, that can aggregate the information taken from the actual smart things themselves.

Notice you might want to store information locally in your data center initially and then move it to the cloud for the ultimate storage and for more long-term things, like trend analysis and more detailed analysis. This might even include some machine learning.

So remember, fog computing is intelligence and processing that we’re going to do pretty close to the devices themselves. But edge computing would be an IoT reference, where we’re even closer to those devices. In fact, this is often implemented in the devices themselves, making them smart devices that are capable of computing and processing.

Thanks for reading!

Enjoy an Intro Nugget on Kubernetes

December 5, 2018 at 12:04 am

Enjoy this sample Nugget from the CBT Nuggets course Cisco CCIE RS Core Concepts – Evolving Technologies https://www.cbtnuggets.com/it-training/cisco-ccie-concepts-evolving-technologies This course was released in November of 2018 and covers everything you need to know to handle the Evolving Technologies questions in all CCIE Written Certification exams as well as the CCDE qualification exam. This video provides an introduction to Kubernetes – a clustering technology that is taking the world by storm. These clusters permit the deployment of containers. These containers often represent micro-services deployed in a cloud-based infrastructure. These micro-service work together to bring robust applications to end users.

For a full list of all of the great Nuggets in this course – check out this link.

Cisco CCIE RS Core Concepts – Evolving Technologies Arriving at CBT Nuggets

November 29, 2018 at 9:37 am

Evolving Technologies

All Nuggets are complete for one of the most requested courses in my five-year history with CBT Nuggets! The course is now in the review process at CBT Nuggets and I expect the course to release in the next couple of business days to our site. This course details EVERY bullet and sub-bullet point of the latest Evolving Technologies section for CCIE written exams as well as the CCDE qualification exam. If you would like the PDF of these objectives – just click here.

Nugget in this course consist of the following titles:

  1. Cloud Benefits and Vendors
  2. Cloud Deployment and Service Models
  3. Performance in the Cloud
  4. Scalability in the Cloud
  5. High Availability in the Cloud
  6. Security Policies and Compliance
  7. Encryption and Tunneling
  8. Securing the Infrastructure
  9. Securing a Cloud Service Model
  10. Security Automation
  11. Workload Migrations
  12. Workload Migration Considerations
  13. Virtual Machines
  14. Hypervisors
  15. Installing the ESXi Hypervisor
  16. Virtual Switches
  17. Introducing Containers
  18. Running Containers
  19. SD-Access
  20. SD-WAN
  21. Virtualization Functions
  22. Automation and Orchestration
  23. CloudCenter and DNA Center
  24. Kubernetes
  25. XML and JSON
  26. YANG and NETCONG
  27. RESTCONF and gRPC
  28. Version Control Systems
  29. SDN: Policy Driven Configuration
  30. SDN: Northbound and Southbound APIs
  31. Agent and Agent-less Config Mgmnt Tools
  32. Introducing the IoT
  33. IoT Technologies
  34. IoT Technology Stacks
  35. The Common IoT Model
  36. IoT Security
  37. IoT Edge and Fog Computing

CCIE and CCDE Evolving Technologies Study Guide Book Review

November 27, 2018 at 7:58 pm

Evolving Technologies

It sure felt strange clicking Add to Cart for an ebook priced at $119.99. In fact, to be honest, it felt absurd. We cannot blame the authors, in the Pearson realm, you get zero input on book price.

I presume the logic here was – CCIE or CCDE candidates will pay more – a lot more – for their preparation products. I actually would not have been complaining here too much about the price had I been able to receive a print copy of the book as well. But sure enough – nothing. At 264 pages – the print book would not have been that short.

OK, I will shut up now about price and get into the review. This book certainly deserves it – because overall – it is really, really great!

Brad EdgeworthJason Gooley, and Ramiro Garza Rios (darn big deals in our industry) succeed here at doing what many of us (myself included) have failed at doing – in my opinion, they cover these evolving technologies in just the right level of detail we need and expect for our written exam pursuits. 

Here is a summary of my thoughts. We will start with the GOOD and quickly recap the few BAD.

THE GOOD

  • Having taken many (to say the least) of these exams that include Evolving Technology questions, it felt to me as if this book really does cover any area we might get poked in during an exam. Like all Cisco exams, you can feel a bit off balance with the question pool for a topic domain. You might get one ridiculously simple question on the cloud to see if you know what SaaS is all about, but then the very next question is asking you some very detailed question about orchestration using a Cisco tool. This book really seems to cover us no matter what Cisco throws our way. NOTE: Be sure to make flashcards covering the many, many details that are in these pages. Perhaps it is protocols in a table (IoT) in the book where you might get questions. So avoid the temptation of not REALLY studying this material.
  • The book contains some really fun and interesting hands-on work you can perform yourself and follow along with. This was a pleasant and unexpected surprise in a text of this nature.
  • This book is clearly not a copy paste from other materials. The tone and accessible language of the text really demonstrate that the authors each really knew their stuff for the respective sections and just explained these new technologies to us in a manner that made it a snap to understand.
  • Related to the previous bullet, the length of this text just feels spot on. Could you write this same text and have it consume Stephen King type length? Of course you could, but that would not serve students well!

THE BAD

  • I am not sure why the authors decided to not follow the blueprint order of topics letter for letter. Why move IoT to the first section when it is the last section of the blueprint? Why not have subsections named after the sub-bullets from the blueprint? I am convinced that every objective is actually covered and covered well in this text, it just would have been easier to find stuff if it mirrored the blueprint PDF.
  • No printed copy sure is a bummer. While I will do a Kindle or an iPad when forced to – I am old school – give me a book any day. In fact, especially for Cisco Press content.

While researching this post, I realize that buying it on Amazon was probably a mistake as it is locked up tight on my Kindle and I have already run into licensing issues trying to read it on my millions of screens. Over at Pearson IT Certification, it is cheaper and available in a PDF format.

http://www.pearsonitcertification.com/store/ccie-and-ccde-evolving-technologies-study-guide-9780789759726

CCIE DC – 1.1.a Link Aggregation – Virtual Port Channel Example

October 2, 2018 at 11:18 pm

This post examines a sample configuration of a virtual port channel. This port channel is created between two Nexus 7K systems and downstream Nexus 5K systems. This is part of the link aggregation section of the exam requirements in CCIE Data Center. Below is the diagram you can use for reference in this example. We will only demonstrate the config of a single VPC peer since the other peer is simply a mirror of this configuration.

Virtual Port Channel

Our previous post on this subject focused on the configuration steps. You can find it here: https://www.ajsnetworking.com/ccie-dc-1-1-a-link-aggregation-configure-virtual-port-channels/

The Configuration

First, we will prepare the vPC keepalive link for this scenario. Do not be thrown off by the name of our VRF. This configuration does not technically fall under the vPC config (yet!).

N7K-A# configure terminal
N7K-A(config)#  vrf context VPC-KEEPALIVE
N7K-A(config-vrf)# interface ethernet 3/18
N7K-A(config-if)# no switchport
N7K-A(config-if)# vrf member VPC-KEEPALIVE
Warning: Deleted all L3 config on interface Ethernet3/18
N7K-A(config-if)# ip addr 209.165.200.225/24

Next, we will configure the vPC domain (after enabling the feature of course) and configure the peer-keepalive link we prepped.

N7K-A(config)# feature vpc
N7K-A(config)# vpc domain 10
N7K-A(config-vpc-domain)# peer-keepalive destination 209.165.200.226 source 209.165.200.225 vrf VPC-KEEPALIVE

Now, we configure a port channel between our vPC peers and configure it as the vPC peer link.

N7K-A(config-vpc-domain)# interface ethernet 3/16-17
N7K-A(config-if)# channel-group 10
N7K-A(config-if)# interface port-channel 10
N7K-A(config-if)# vpc peer-link

Next, we will head down to the N5K and configure a “plain ole” LACP port channel.

N5K-A# config t
N5K-A(config)# feature lacp
N5K-A(config)# int e 1/1-2
N5K-A(config-if-range)# channel-group 201 mode active

Now, it is time to configure the vPC on the N7K.

N7K-A(config-if)# feature lacp
N7K-A(config)# interface e 3/21
N7K-A(config-if)# channel-group 201 mode active
N7K-A(config-if)# int port-channel 201
N7K-A(config-if)# vpc 201

The Verification

You should note that you can and should perform verifications as you go along here. For example, you can verify reachability, check the port channels that are configured, and watch the progress of the vPC as you configure it. For brevity here, we will just end this post and this example with our critical show vpc command.

N7K-A(config-if)# show vpc brief
Legend:
     (*) - local vPC is down, forwarding via vPC peer-link

vPC domain id                          : 10
Peer status                            : peer adjacency formed ok
vPC keep-alive status                  : peer is alive
Configuration consistency status       : success
Per-vlan consistency status            : success
Type-2 consistency status              : success
vPC role                               : secondary
Number of vPCs configured              : 1
Peer Gateway                           : Disabled
Dual-active excluded VLANs and BDs     : -
Graceful Consistency Check             : Enabled
Auto-recovery status                   : Enabled (timeout = 240 seconds)
Operational Layer3 Peer-router         : Disabled
Self-isolation                         : Disabled

vPC Peer-link status
--------------------------------------------------------------------------------
id Port Status  Active vlans Active BDs
-- ---- ------ -------------------------------------------------------------
1  Po10 up      1,12 -

vPC status
------------------------------------------------------
id     Port        Status Consistency  Active VLANs
----- ------------ ------ ----------- ----------------
201    Po201       up      success     1,12

For even more information – check out this Cisco documentation at https://www.cisco.com/c/en/us/products/collateral/switches/nexus-5000-series-switches/design_guide_c07-625857.html
Pearson Education (InformIT)

CCIE DC Written – 1.1.a Link Aggregation – LACP

September 20, 2018 at 2:05 am

NX-OS

Here are some Nexus facts to keep in mind:

  • With LACP, you can bundle up to 16 interfaces in a channel group. If the channel group has more than 8 interfaces, the remaining interfaces are in hot standby for the port channel associated with this channel group on the M-series modules.
  • From Cisco NX-OS Release 5.1, you can bundle up to 16 active links into a port channel on the F-series module.
  • When you delete the port channel, the software automatically deletes the associated channel group. All member interfaces revert to their original configuration.
  • You cannot disable LACP while any LACP configurations are present.
  • When you run static port channels with no aggregation protocol, the channel mode is always set to on.

Of course, you must globally enable LACP before you can use it on the Nexus device. There are two modes:

  • Passive – responds to negotiations, but does not initiate them – sounds like me at the High School dance
  • Active – initiates negotiations

Starting at 4.2(3) – Cisco introduced some LACP compatibility enhancements as follows:

  •  When a Cisco Nexus device is connected to a non-Nexus peer, its graceful failover defaults may delay the time taken for a disabled port to be brought down or cause traffic from the peer to be lost. To address these conditions, the lacp graceful-convergence command was added.
  • By default, LACP sets a port to the suspended state if it does not receive an LACP PDU from the peer. In some cases, although this feature helps in preventing loops created due to misconfigurations, it can cause servers to fail to boot up because they require LACP to logically bring up the port. You can put a port into an individual state by using the lacp suspend-individual command.

Starting with Release 5.1 Cisco introduced the Minimum Links feature as well as MaxBundle. The Minimum Links feature allows you to:

  • Configure the min number of links that must be in the bundle
  • Prevent low bandwidth LACP bundles from becoming available
  • Causes the port channel to go inactive if the required min bandwidth is not available

MaxBundle allows:

  • Upper limit on ports that are bundled
  • Allows the designation of ports as hot standby

Basic Configuration

  • Use feature lacp to enable the feature
  • Create the port channel interface with interface port-channel 10, use the switchport command in the interface
  • Add a Layer 2 interface to the port channel with switchport followed by channel-group 10 mode passive