40 – DCNM 11.1 and VRF-Lite connection to an external Layer 3 Network

Another great feature supported by DCNM concerns the extension of Layer 3 connection across an external Layer 3 network using VRF-Lite hand-off from the Border leaf node toward the external Edge router.

There are different options to deploy a VRF-Lite connection to the outside of the VXLAN fabric. Either using a manual deployment or leveraging the auto-configuration process that will configure automatically the VRF-lite toward the Layer 3 network.

One of the key reasons for configuring the interfaces manually is when the Layer 3 network is managed by an external service provider, thus the Network team has no control on the configuration which is imposed by the Layer 3 service operator.

The first demo illustrates an end-to-end manual configuration of VRF-Lite connections from the Border leaf node to an external Edge router.

The Border leaf nodes being a vPC domain, the recommendation is to configure a interface per vPC peer device connecting the external Layer 3 network. As a result, I configured 1 “inter-fabric” type link per Border Gateway.

Prior to deploy the external VRF-lite, an external fabric must be created in which the concerned Edge router should be imported. For this particular scenario, because the Network team is not Continue reading

Campus design feature set-up : Part 1

Shared knowledge makes for a stronger ecosystem and with this in mind, I’m going to show you how to set up the CL 3.7.5 campus feature: Multi-Domain Authentication in a 6-part blog series. 

We’ll cover it all: Wired MAC Authentication using Aruba ClearPass, Multi-Domain Authentication using Aruba ClearPass, Wired 802.1x using Cisco ISE, Wired MAC Authentication using Cisco ISE, and Multi-Domain Authentication using Cisco ISE. 

The first guide I’ll be sharing is how to enable wired 802.1X authentication in Cumulus Linux 3.7.5+ using Aruba ClearPass 6.7.x. 

Keep in mind that this step-by-step guide assumes that you have already performed an initial setup of Aruba ClearPass.

Aruba ClearPass Configuration:

1. Add the Cumulus Switch to ClearPass

First, we are going to add this specific Cumulus Network switch to ClearPass. Go to the following:

Configuration > Network > Devices. Click “+Add” in the top right-hand corner

Fill in the appropriate IP Address, Description, and Shared Secrets. For simplicity sake, set the “Vendor Name” to “Cisco.”

2. Adding the Cumulus Switch to a Device Group

Configuration > Network  > Device Groups. Click “+Add” in the top right-hand corner

We are Continue reading

MySQL High Availability Framework Explained – Part III: Failover Scenarios

MySQL High Availability Framework Explained – Part III: Failover Scenarios

In this three-part blog series, we introduced a High Availability (HA) Framework for MySQL hosting in Part I, and discussed the details of MySQL semisynchronous replication in Part II. Now in Part III, we review how the framework handles some of the important MySQL failure scenarios and recovers to ensure high availability.

MySQL Failover Scenarios

Scenario 1 – Master MySQL Goes Down

  • The Corosync and Pacemaker framework detects that the master MySQL is no longer available. Pacemaker demotes the master resource and tries to recover with a restart of the MySQL service, if possible.
  • At this point, due to the semisynchronous nature of the replication, all transactions committed on the master have been received by at least one of the slaves.
  • Pacemaker waits until all the received transactions are applied on the slaves and lets the slaves report their promotion scores. The score calculation is done in such a way that the score is ‘0’ if a slave is completely in sync with the master, and is a negative number otherwise.
  • Pacemaker picks the slave that has reported the 0 score and promotes that slave which now assumes the role of master MySQL on which writes are allowed.
  • After Continue reading

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BrandPost: Two tools to help visualize and simplify your data-driven operations

Build the picture: Visualize your dataThe Internet of Things (IoT), 5G, smart technology, virtual reality – all these applications guarantee one thing for communications service providers (CSPs): more data.  As networks become increasingly overwhelmed by mounds of data, CSPs are on the hunt for ways to make the most of the intelligence collected and are looking for ways to monetize their services, provide more customizable offerings, and enhance their network performance.Customer analytics has gone some way towards fulfilling this need for greater insights, but with the rise in the volume and variety of consumer and IoT applications, the influx of data will increase at a phenomenal rate. The data includes not only customer-related data, but also device and network data, adding complexity to the picture. CSPs must harness this information to understand the relationships between any two things, to understand the connections within their data and to ultimately, leverage it for a better customer experience.To read this article in full, please click here

Five Functional Facts about AWS Identity and Access Management

This post is part of an open-ended series I’m writing where I take a specific protocol, app, or whatever-I-feel-like and focus on five functional aspects of that thing in order to expose some of how that thing really works.

The topic in this post is the AWS Identity and Access Management (IAM) service. The IAM service holds a unique position within AWS: it doesn’t get the attention that the machine learning or AI services get, and doesn’t come to mind when buzzwords like “serverless” or “containers” are brought up, yet it’s used by–or should be used by–every single AWS customer (and if you’re not using it, you’re not following best practice, tsk, tsk) so it’s worthwhile to take the time to really get to know this service.

Let’s begin!

1 – The root user supersedes IAM policies

The main reason I threw a bit of shade about following best practice and always using IAM has to do with the root user in an account. The root user is what’s created when a new AWS account is opened. The username for the root user is always an email address and the root user is able to log into the AWS account Continue reading

Using Kubeadm to Add New Control Plane Nodes with AWS Integration

In my recent post on using kubeadm to set up a Kubernetes 1.13 cluster with AWS integration, I mentioned that I was still working out the details on enabling AWS integration (via the AWS cloud provider) while also using new functionality in kubeadm (specifically, the --experimental-control-plane flag) to make it easier to join new control plane nodes to the cluster. In this post, I’ll share with you what I’ve found to make this work.

The challenge here, by the way, is that you can’t use the --config <filename>.yaml flag and the --experimental-control-plane flag at the same time. I did try this, and the results of my testing led me to believe that although kubeadm doesn’t report an error, it does ignore the --experimental-control-plane flag. (Kubernetes experts/contributors, feel free to let me know if I’ve missed something here.)

After some trial-and-error—mostly my own fault because I didn’t take the time to review the v1beta1 kubeadm API docs ahead of time—I finally arrived at a working configuration that allows you to use kubeadm join --config <filename>.yaml to join a control plane node to an existing AWS-integrated Kubernetes cluster.

Credit for finding the solution goes to Rafael Fernández López, Continue reading

Online Trust Audit Finds Better Email Authentication and Encryption; Worse Privacy Statement Scores

Do you know how – or even if – your favorite retailer, or your bank, or your ISP is working to protect you? The Online Trust Alliance recognizes excellence in consumer protection, data security and responsible privacy practices. Today, we released the 10th annual Online Trust Audit & Honor Roll, covering more than 1,200 predominantly consumer-facing websites, and found that 70% of the websites we analyzed qualified for the Honor Roll. That’s the highest proportion ever, driven primarily by improvements in email authentication and session encryption.

Highlights

Overall, we found a strong move toward encryption, with 93% of sites encrypting all web sessions. Email authentication is also at record highs; 76% use both SPF and DKIM (which prevent spoofed/forged emails) and 50% have a DMARC record (which provides instruction on how to handle messages that fail authentication).

It’s not all good news, though. We also found that only 11% of organizations use mechanisms for vulnerability reporting, which allows users to report bugs and security problems. Only 6% use Certificate Authority Authorization, which limits certificate abuse. And overall privacy scores dropped compared to last year, primarily due to more stringent scoring in light of the E.U.’s General Continue reading

What SDN is and where it’s going

Hardware reigned supreme in the networking world until the emergence of software-defined networking (SDN), a category of technologies that separate the network control plane from the forwarding plane to enable more automated provisioning and policy-based management of network resources.SDN's origins can be traced to a research collaboration between Stanford University and the University of California at Berkeley that ultimately yielded the OpenFlow protocol in the 2008 timeframe. [Learn more about the difference between SDN and NFV. Get regularly scheduled insights by signing up for Network World newsletters] OpenFlow is only one of the first SDN canons, but it's a key component because it started the networking software revolution. OpenFlow defined a programmable network protocol that could help manage and direct traffic among routers and switches no matter which vendor made the underlying router or switch. To read this article in full, please click here

REST API Is Not Transactional

This blog post was initially sent to subscribers of my SDN and Network Automation mailing list. Subscribe here.

I was walking down the infinite hallways of Cisco Live Europe chatting with the fellow Tech Field Day Extra delegates when I probably blanked out for a minute as the weirdest of thoughts hit me: “REST API is not transactional”

TL&DR: Apart from using structured data and having error codes REST API is functionally equivalent to Cisco IOS CLI from 1995

Read more ...

How to deal with backup when you switch to hyperconverged infrastructure

Companies migrating to hyperconverged infrastructure (HCI) systems are usually doing so to simplify their virtualization environment. Since backup is one of the most complicated parts of virtualization, they are often looking to simplify it as well via their migration to HCI.Other customers have chosen to use HCI to simplify their hardware complexity, while using a traditional backup approach for operational and disaster recovery. Here’s a look at cover both scenarios.To read this article in full, please click here

How to deal with backup when you switch to hyperconverged infrastructure

Companies migrating to hyperconverged infrastructure (HCI) systems are usually doing so to simplify their virtualization environment. Since backup is one of the most complicated parts of virtualization, they are often looking to simplify it as well via their migration to HCI.Other customers have chosen to use HCI to simplify their hardware complexity, while using a traditional backup approach for operational and disaster recovery. Here’s a look at cover both scenarios.To read this article in full, please click here

More DOH

DOH is not going away. It seems that the previous article on DOH has generated some reaction, and also there is some further development that should be reported, all of which I'll cover here.

Five Functional Facts about AWS Identity and Access Management

This post is part of an open-ended series I'm writing where I take a specific protocol, app, or whatever-I-feel-like and focus on five functional aspects of that thing in order to expose some of how that thing really works.

The topic in this post is the AWS Identity and Access Management (IAM) service. The IAM service holds a unique position within AWS: it doesn't get the attention that the machine learning or AI services get, and doesn't come to mind when buzzwords like “serverless” or “containers” are brought up, yet it's used by-or should be used by-every single AWS customer (and if you're not using it, you're not following best practice, tsk, tsk) so it's worthwhile to take the time to really get to know this service.

Let's begin!

How to identify duplicate files on Linux

Identifying files that share disk space relies on making use of the fact that the files share the same inode — the data structure that stores all the information about a file except its name and content. If two or more files have different names and file system locations, yet share an inode, they also share content, ownership, permissions, etc.These files are often referred to as "hard links" — unlike symbolic links that simply point to other files by containing their names. Symbolic links are easy to pick out in a file listing by the "l" in the first position and -> symbol that refers to the file being referenced.$ ls -l my* -rw-r--r-- 4 shs shs 228 Apr 12 19:37 myfile lrwxrwxrwx 1 shs shs 6 Apr 15 11:18 myref -> myfile -rw-r--r-- 4 shs shs 228 Apr 12 19:37 mytwin Identifying hard links in a single directory is not as obvious, but it is still quite easy. If you list the files using the ls -i command and sort them by inode number, you can pick out the hard links fairly easily. In this type of ls output, the first column shows the inode numbers.To read Continue reading

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