Feedback: Designing Active/Active and Disaster Recovery Data Centers
In the Designing Active-Active and Disaster Recovery Data Centers I tried to give networking engineers a high-level overview of challenges one might face when designing a highly-available application stack, and used that information to show why the common “solutions” like stretched VLANs make little sense if one cares about application availability (as opposed to auditor report). Some (customer) engineers like that approach; here’s the feedback I received not long ago:
As ever, Ivan cuts to the quick and provides not just the logical basis for a given design, but a wealth of advice, pointers, gotchas stemming from his extensive real-world experience. What is most valuable to me are those “gotchas” and what NOT to do, again, logically explained. You won’t find better material IMHO.
Please note that I’m talking about generic multi-site scenarios. From the high-level connectivity and application architecture perspective there’s not much difference between a multi-site on-premises (or collocation) deployment, a hybrid cloud, or a multicloud deployment.
Selector is evolving the way we operate networks
The topic of AI in the networking space has quickly moved from “what if” to “how soon”. Every major networking vendor is leveraging some aspect of...
The post Selector is evolving the way we operate networks appeared first on /overlaid.
What Ukraine’s IT Industry Can Teach CIOs About Resilience
War has tested Ukraine's cyber resilience in unimaginable ways. Yet, by rising to the challenge, the Ukrainian IT industry has emerged as a leader in the country’s new economy. Data shows growth in the tech sector and suggests further reasons for optimism in the coming year.CE-to-CE IBGP Session in a Multihomed Site
One of my readers sent me a question along these lines:
Do I have to have an IBGP session between Customer Edge (CE) routers in a multihomed site if they run EBGP with the upstream provider(s)?
Let’s start with a simple diagram and a refactoring of the question:
CE-to-CE IBGP Session in a Multihomed Site
One of my readers sent me a question along these lines:
Do I have to have an IBGP session between Customer Edge (CE) routers in a multihomed site if they run EBGP with the upstream provider(s)?
Let’s start with a simple diagram and a refactoring of the question:
Anuta Networks Adds Synthetic Tests For On-Demand Network Performance Monitoring
Anuta Networks has added an active assurance capability to ATOM, its network automation and orchestration software. Active assurance lets engineers run synthetic tests on demand using software agents. For example, if a service provider wants to test the performance of a link or network segment to see if it’s meeting SLAs, it can run a […]
The post Anuta Networks Adds Synthetic Tests For On-Demand Network Performance Monitoring appeared first on Packet Pushers.
Upcoming Course: How Routers Really Work
I’m teaching a course on router internals over at Safari Books Online on the 24th (in 10 days). From the descriptions:
A network device—such as a router, switch, or firewall—is often seen as a single “thing,” an abstract appliance that is purchased, deployed, managed, and removed from service as a single unit. While network devices do connect to other devices, receiving and forwarding packets and participating in a unified control plane, they are not seen as a “system” in themselves.
The course is three hours. I’m in the process of updating the slides … or rather, I need to get to updating the slides in the next couple of days.
Real-time flow analytics with Containerlab templates
This article describes an experiment with Containerlab's advanced Generated topologies capability, taking the 3 stage Clos topology shown above and creating a template that can be used to generate topologies with any number of leaf and spine switches.
The clos3.yml topology file specifies the 2 leaf 2 spine topology shown above:
name: clos3
mgmt:
network: fixedips
ipv4_subnet: 172.100.100.0/24
ipv6_subnet: 2001:172:100:100::/80
topology:
defaults:
env:
COLLECTOR: 172.100.100.8
nodes:
leaf1:
kind: linux
image: sflow/clab-frr
mgmt_ipv4: 172.100.100.2
mgmt_ipv6: 2001:172:100:100::2
env:
LOCAL_AS: 65001
NEIGHBORS: eth1 eth2
HOSTPORT: eth3
HOSTNET: "172.16.1.1/24"
HOSTNET6: "2001:172:16:1::1/64"
exec:
- touch /tmp/initialized
leaf2:
kind: linux
image: sflow/clab-frr
mgmt_ipv4: 172.100.100.3
mgmt_ipv6: 2001:172:100:100::3
env:
LOCAL_AS: 65002
NEIGHBORS: Continue reading
Managed Services Can Offset IT Burdens From An Explosion of Mobile Devices
The vast number of connected devices enterprises must support today creates a problem that’s been brewing for a while but has now hit a tipping point.Twenty-five open-source network emulators and simulators you can use in 2023
I surveyed the current state of the art in open-source network emulation and simulation. I also reviewed the development and support status of all the network emulators and network simulators previously featured in my blog.
Of all the network emulators and network simulators I mentioned in my blog over the years, I found that eighteen of them are still active projects. I also found seven new projects that you can try. See below for a brief update about each tool.
Active projects
Below is a list of the tools previously featured in my blog that are, in my opinion, still actively supported.
Cloonix
Cloonix version 28 was released in January 2023. Cloonix stitches together Linux networking tools to make it easy to emulate complex networks by linking virtual machines and containers. Cloonix has both a command-line-interface and a graphical user interface.
The Cloonix web site now has a new address at: clownix.net and theCloonix project now hosts code on Github. Cloonix adopted a new release numbering scheme since I reviewed it in 2017. So it is now at “v28”.
Cloudsim
CloudSim is still maintained. Cloudsim is a network simulator that enables modeling, simulation, and experimentation of emerging Cloud computing Continue reading
MUST READ: Machine Learning for Network and Cloud Engineers
Javier Antich, the author of the fantastic AI/ML in Networking webinar, spent years writing the Machine Learning for Network and Cloud Engineers book that is now available in paperback and Kindle format.
I’ve seen a final draft of the book and it’s definitely worth reading. You should also invest some time into testing the scenarios Javier created. Here’s what I wrote in the foreword:
Artificial Intelligence (AI) has been around for decades. It was one of the exciting emerging (and overhyped) topics when I attended university in the late 1980s. Like today, the hype failed to deliver, resulting in long, long AI winter.
MUST READ: Machine Learning for Network and Cloud Engineers
Javier Antich, the author of the fantastic AI/ML in Networking webinar, spent years writing the Machine Learning for Network and Cloud Engineers book that is now available in paperback and Kindle format.
I’ve seen a final draft of the book and it’s definitely worth reading. You should also invest some time into testing the scenarios Javier created. Here’s what I wrote in the foreword:
Artificial Intelligence (AI) has been around for decades. It was one of the exciting emerging (and overhyped) topics when I attended university in the late 1980s. Like today, the hype failed to deliver, resulting in long, long AI winter.