One of my readers sent me an email that’s easiest paraphrased into: “Why can’t I have a different IPv6 link-local address (LLA) on every access port connected to a VLAN interface?”

There’s probably nothing stopping someone from implementing such an approach, but it would go against the usual understanding of how bridging and routing interact in L2+L3 switches.

I got tons of questions about the upcoming Building Network Automation Solutions online course. It always starts with the same one:

Is access to the self-study material granted upon enrollment?

Absolutely. You also get access to everything we did in January, and the new self-paced Ansible for Networking Engineers online course.

Have you ever wondered what the difference between automation and orchestration is?

Wikipedia defines automation as use of various control systems for operating equipment. The definition I prefer (because it’s easier to understand in network automation environment) is elimination of well-defined repeatable manual tasks – the emphasis being on well-defined and repeatable.

Another question from someone watching my Designing Active-Active and Disaster Recovery Data Centers webinar (you know, the one where I tell people how to avoid the world-spanning-layer-2 madness):

In the video about parallel application stacks (swimlanes) you mentioned that one of the options for using the R/W database in Datacenter A if the user traffic landed in Datacenter B in which the replica of the database is read-only was to redirect the user browser with the purpose that the follow up HTTP POST land in Datacenter A.

Here’s the diagram he’s referring to:

Here’s the list of materials (and other changes) I added to the Ansible for Networking Engineers webinar and online course in June 2017.

The first thing you’ll notice is the brand-new user interface with collapsible sections, making it easier to grasp the big picture (the change was badly needed – the webinar is already almost 12 hours long).

Got this remark from one of my SDN mailing list subscribers:

There are NMSs that are based on SNMP, their manufacturers that say they can replace an SDN architecture, because they allow to automate the management of the network.

O’RLY?

I get a “how do I get started with network automation” question every other week, and when I wrote a lengthy reply to one about configuration templating of existing snowflake network on networktocode Slack channel I decided it’s time to turn my replies into a blog post.

Here’s the question I got from one of my readers:

Do you have any data available to show the benefits of jumbo frames in 40GE/100GE networks?

In case you’re wondering why he went down this path, here’s the underlying problem:

Johannes Weber published the solutions to his Wireshark challenges. How many did you solve?

I developed over a dozen different Ansible-based network automation solutions in the last two years for my network automation workshops and online course, and always published them on GitHub… but never built an index, or explained what they do, and why I decided to do things that way.

With the new my.ipSpace.net functionality I added for online courses I got the hooks I needed to make the first part happen:

One of my readers sent me a list of questions on asymmetrical traffic flows in IP networks, particularly in heavily meshed environments (where it’s really hard to ensure both directions use the same path) and in combination with stateful devices (firewalls in particular) in the forwarding path.

Unfortunately, there’s no silver bullet (and the more I think about this problem, the more I feel it’s not worth solving).

The inevitable summer decline of visitors has started, so I'm switching (like every summer) to a lower publishing frequency. Given my current focus (here and here) expect one network automation post and one other in-depth post every week… and maybe an occasional this-is-worth-reading link.

Working in the summer office ;)

Take some time off, enjoy the vacations, and I hope to meet you in the September online course ;)

Monitoring SDN Networks is the featured webinar of June 2017, and in the featured video Terry Slattery (CCIE#1026) talks about network analysis of SDN.

If you’re a trial subscriber, log into my.ipspace.net, select the webinar from the first page, and watch the video marked with star… and if you’d like to try the ipSpace.net subscription register here.

Trial subscribers can also use this month's featured webinar discount to get a 25% discount (and get closer to the full subscription).

Another part of my data center infrastructure optimization presentation is transcribed, edited and published: use distributed file system (at least for VM disk images).

Today I can tell you who the first speakers in the autumn 2017 network automation online course will be.

• Patrick Ogenstad (author of numerous open-source network automation modules and libraries) will talk about his journey to network automation, and lessons learned on the way.
• David Barroso will talk about his newest project: support of OpenConfig in NAPALM and Ansible (also discussed on a recent podcast).

Sounds promising? Why don’t you register before we run out of early-bird tickets?