I just played with the same example and I get the same response as you if I stop my netsim devcies and then try to re-connect.
try "ncs-netsim status" and see if they are started.
info Failed to connect to device c2: connection refused: Connection refused
admin@ncs> *** ALARM connection-failure: Failed to connect to device c1: connection refused: Connection refused
... View more
Every once in a while I get a craving to install and run some NSO examples just to keep my basic knowledge at a bare minimum. This time I responded to an ask to test out our updated NSO getting started guide. Downloading and installing is seldom an issue and now it was smooth as it’s is free for evaluation and the link is provided on DevNet. You can even Google it if you can’t find it! Following the step-by-step guide is really fun and you almost feel like a developer, which I was 20 years ago. This time though my problems started already when running the first examples with Netsims. First, I could not ssh into the CLI, but who cares when there are other ways in (ncs_cli -u admin), but when I couldn’t connect to the devices or do sync from I was stuck. I realized that it had to do with SSH in one way or another. I am not an expert in this area and suddenly recalled why I left engineering. Stubborn as I am, I tried too many times and after repeated failures I got angry. When my colleague asked me how the review process was going I had to admit my defeat and finally asked for help. Luckily, we have an internal channel and when I broadcasted by SSH shortcomings, I had an answer to my problems within 60 seconds! This fast response was due to several people contributing to the solution before me and I just got their conclusions in a nice summary. After a bit of fiddling with new key generation I was back on track! It turned out to be a shortcoming of the NSO installation program that failed to recognize the new key format in OpenSSH version that comes with Mojave!
Think about how much time and effort you can save by using collective intelligence in a community, but don’t forget that your contribution matters! Writing this blog post is my contribution!
The example I was running: /examples.ncs/getting-started/using-ncs/1-simulated-ciso-ios
The error message: Unable to negotiate with 127.0.0.1 port 2024: no matching host key type found. Their offer:
* ssh-keygen(1): write OpenSSH format private keys by default instead of using OpenSSL's PEM format. The OpenSSH format, supported in OpenSSH releases since 2014 and described in the PROTOCOL.key file in the source distribution, offers substantially better protection against offline password guessing and supports key comments in private keys. If necessary, it is possible to write old PEM-style keys by adding "-m PEM" to ssh-keygen's arguments when generating or updating a key.
So, generate new keys in your install directory (in both NSO and Netsim directories) with -m pem and you will be back to normal.
NWAGERTH-M-L58X:ssh nwagerth$ ssh-keygen -m pem -f ssh_host_rsa_key
Generating public/private rsa key pair.
ssh_host_rsa_key already exists.
Overwrite (y/n)? y
Enter passphrase (empty for no passphrase):
Enter same passphrase again:
Your identification has been saved in ssh_host_rsa_key.
Your public key has been saved in ssh_host_rsa_key.pub.
The key fingerprint is:
... View more
Big thanks to all who attended and contributed to our second annual NSO Developer Connect in New York City. You all made it a truly great event!
We literally had to remove the tables from the largest room at the Cisco Manhattan office to fit chairs for all of you. 41 NSO users from 19 different companies from both service providers and enterprise joined the open discussion together with 30 NSO experts from Cisco.
Every Automation Journey is unique but we have much in common stated John Clowers, who led the user experience sharing session with the help of an NSO expert panel. We do seem to agree on the most important things:
It’s not only about selecting the God Tool, as one called out.
Automation teams have to include networking and software skills.
All stakeholders need to be involved
Sometimes the devil is in the details, and sometimes you can’t see the forest for all the trees. It depends on how you look at things and we find it helpful to have these two metaphors in mind while navigating toward our goals.
When starting up an NSO project it can be hard to see how to make the best of the different skills in the team. Kevin Corbin kicked off the day by giving some examples of what NSO means for the networking guy. One example was the big savings that can be made in the day-to-day work by using a single favorite CLI to all network devices, in contrast to learning many CLIs. Another advantage is that the NSO CLI is, in fact, an API, just like NETCONF! Kevin also talked about how Network Engineering is changing from an art of “figuring out what command to run on which device and when” to a structured process using Consistent Version Controlled Infrastructure deployed with Parallel & Automated Provisioning (e.g. NetDevOps). Can you see where we are going? Viktor Leijon continued from a software-centric point of view discussing how basic software practice can be used in Network Automation. Simple things like using version control, taking small incremental steps instead of giant leaps and automating your tests make a huge difference. Viktor has long experience from working side by side with Network Engineers and his interest in how we work has helped him understand how software practice is best used in networking. A very nice side effect of a model-based framework like NSO is that you can minimize the coding and automate the manual, boring work and focus on what makes your company unique. Which approach would you choose?
After lunch, we broke up into two tracks. The experienced technical track wanted to go deep and Sebastian Strollo and team did not let anyone down! With so much knowledge in the same room, no question was untouched, but there are always limits in what you can cover in a half day. For those of you looking for, even more, Stockholm and Developer Days is the place to visit in June of 2019!
While engineers were having fun, managers broke out together with Fredrik Swahn into a managerial track discussing people, process and the many aspects of leading change towards automation. The focus was to share experience, both good and bad. All projects are different and we have different levels of experience. What surprises me each time, is how sharing comes easy in small, informal environments regardless of where you come from. We don’t share company secrets but we share ways of working and learn from each other. Clearly, there is a great need for sharing. Once the discussion was going it was hard to stop. This is how we want the NSO community to work for you.
Shafi Ambattuparambil concluded the first day with adding some perspectives using the Red Whale metaphor to show the importance to do things right from start and build a sustainable solution that can be maintained and supported over time throughout the organization. It’s important to work together selecting the use cases and include all stakeholders. Cisco comes ready with CX Advisory Services to help connect the top-down approach with the bottom-up, drive change management when necessary and help teams secure the right business outcome.
Day 2 was new this year and is our commitment to meet your number one and number two request from previous events:
More time for hands-on.
More time for face to face meetings.
Fredrik Jansson and John Mullooly guided over 20 people through labs learning how to use Ansible with NSO and Cisco vBranch Core Function Pack, while Ashok and the other solutions architects were coordinating one-on-one meetings. Every time I see these labs it strikes me how well contained they are and how easy it looks. You can even continue working in the Cisco dCloud lab at home!
Since NSO Developer Connect meetings are much about, experience sharing and connecting industry peers, they are very informal and difficult to summarize. To get the most out of it you simply have to attend. There is a certain kind of focus that rarely emerge when meetings become too big. This is a key differentiator to full three-day NSO Developer Days event in Stockholm which have all sessions recorded and attendees from all over the globe. But of course, if you want (according to the survey) more of everything we served at the NYC connect, then you have to attend both J.
Anyway, I am very happy that 86% of you considered the event to be a good use of time. Not a single one did think it was not worth coming AND it really made my day. Continuing the discussions in a more social environment in the evening was very pleasant after a long intense day and help continue the motion.
Below you find names, titles, and link to event presentations published on the NSO Developer Hub.
NSO Developer Connect Team:
John Clowers, Sr SEM, Cisco Sales.
Kevin Corbin, NetDevOps Engineer, Cisco Enterprise Sales. The Art of Networking
Viktor Leijon, Technical Leader, NSO BU. NSO Onboarding Best Practice
Sebastian Strollo, Principal Engineer NSO BU. NSO Deep Dive Tech Talk
Fredrik Swhan, Product Owner, NSO BU. Managerial Track
Shafi Ambattuparambil, Senior Solution Architect Cisco CX. Expert Panel and Automation Advisory Services
Fredrik Jansson, Technical Leader, Tail-f BU NFVO Update and Labs
John Mullooly, Distinguished SE, SP CTO (NFVO Update and Labs)
Tomas Mellgren, Director of Engineering, Expert Panel
Dan Sullivan, Technical Solutions Architect, Expert Panel
Ashok Sadasivian, Technical Solutions Architect, SP Sales, meet the engineer
... View more
Shafi uses the Red Whale metaphor to show the importance to do things right from start and build a sustainable solution that can be maintained and supported over time throughout the organization. It’s important to work together selecting the use cases and include all stakeholders. Cisco comes ready with CX Advisory Services to help connect the top-down approach with the bottom-up, drive change management when necessary and help teams secure the right business outcome.
... View more
Kevin Corbin talks about how Network Engineering is changing from an art of “figuring out what command to run on which device and when” to a structured process using Consistent Version Controlled Infrastructure deployed with Parallel & Automated Provisioning. He provides examples of what NSO means for the networking guy and the big savings that can be made in the day-to-day work by using a single favorite CLI to all network devices, in contrast to learning many CLIs. The NSO CLI is, in fact, an API, just like NETCONF!
... View more
Learn how basic software practice can be used in Network Automation. Simple things like using version control, taking small incremental steps instead of giant leaps and automating your tests make a huge difference. Viktor Leijon has long experience from working side by side with Network Engineers and his interest in how we work has helped him understand how software practice is best used in networking. A very nice side effect of a model-based framework like NSO is that you can minimize the coding and automate the manual, boring work and focus on what makes your company unique.
... View more
Abhimanyu, Please register to the waiting list using the link; NSO Developer Connect NYC November 15-16, 2018<> and I will see how we can get you in. Currently all seats are taken. Thanks for reaching out! //Nicklas
... View more
Following the second annual NSO Developer Days conference in Stockholm, we are again hosting NSO Developer Connect in NYC. The common theme for these events is that we package up a smaller set of technical presentations from the NSO Developer Days with experience sharing between industry peers. We do this because we believe there is great value in bringing real-life practitioners together and share experience from the network automation and service orchestration reality. We and your industry peers love to hear how you use NSO and what is working well and if anything can be improved or done in a better or different way.
New for this year is that we will offer the Core Function Pack Lab sessions on day 2.
Read more about the NSO Developer Connect in NYC event in the calendar and don't hesitate to reach out if you are interested to attend. Seats are limited and have already started to fill so hurry up if you plan to attend.
... View more
Sorry for the delay but I had to do some research and go back to the training team to answer your question. Hope this help
Here is what I got:
NSO201 was created as a replacement for NSO100 which was EoLed in May 2018. The NSO100 course datasheet has been removed. A detailed summary of the changes is provided below.
Main changes between NSO100 (now EoL) and NSO201:
· Module 1 is completely restructured for easier introduction into the course. High-level explanation about the NETCONF and
YANG is added to describe the basic concepts of NETCONF and YANG at the beginning.
· Additional lesson Resources and Training is added at the end of Module 1 to include additional resources and training options for students.
· Lab topology is extended with one Cisco NX-OS and one Cisco IOS switch to support additional use cases.
· In Module 2: Model to Model mapping lesson is rewritten using the VLAN service. Lesson describes how Template processing logic creates device-specific configurations from an XML template, how Mapping logic correlates with Template processing. The explanation is based on the VLAN example from the FASTMAP topic
· Additional lab on how to create a simple Loopback template service.
· Additional lab on how to create a VLAN template service.
· Module 4 now includes the NSO Programmability Introduction lesson. Lesson describes which language bindings can be used and how to extend the default mapping logic. It explains how service processing with Python works. New example added of Python and template based service. VLAN SVI service used.
· Additional lab on how to create an L3VPN template service
· Additional lab on how to create an SVI python-template service using Python mapping logic.
· New Module 5 added.
· New lesson Scalability and Performance. It describes HA Cluster communication, Layered Service Architecture and how to address performance limitations
· New lesson Components and Function Packs. It describes common concepts and built-in components. It explains how Function Packs extend NSO functionality and how to do NFV Orchestration with NSO.
· Additional lab on how to use NSO REST API with Postman. It shows how to retrieve data of an existing device, create a new device and delete a device. It shows how to retrieve data of an existing service, create a new service, delete a service and issue commit dry-run query using NSO REST API.
... View more
Following the second annual NSO Developer Days conference in Stockholm, we are again arranging a second, smaller event in New York City to continue the momentum around the NSO automation journey and NSO best practice for those US-based practitioners who were not able to travel to Stockholm. This is an opportunity to meet key people from NSO product development, Product Management team and Subject Matter Experts together with your industry peers.
The focus will be on sharing experience and connect with other people in the NSO community as well as provide technology updates and deep dives. This year we have decided to extend the meeting with an option to attend a ½ a day hands-on lab session or schedule a meet the engineer session.
On the evening of November 15, we will host a dinner event downtown where we can continue the dialogue in a more social environment.
Interested to attend? Respond to this post or reach out your local sales contact to get a personal invite!
AGENDA Nov 15
08:30 - 09:30 Welcome and Key Note
09:30 - 10:30 Round Table Presentations. Share NSO use cases and experience
10:30 - 10:45 Coffee
10:45 - 11:30 Product and Roadmap Updates
11:30 - 12:30 NSO Onboarding Best Practice
01:30 – 3:00 LSA Scaling and Performance
03:00 - 03:15 Coffee
03:15 - 04:00 NFVO
04:00 – 04:30 NFVO use case
-- Optional break-out session: Managerial Track
-- 01:30-04:30 Experience and knowledge sharing. We will select topics based on your feedback.
04:30-05:00 AS Enablement / Advisory Service
05:00 - 05:30 Group Discussion – Lessons learned
Agenda Nov 16
09:00 - 12:00 Core Function Pack Lab
09:00 - 12:00 Option to meet the engineer. Reach out to your sales rep to schedule a slot
12:30 - 13:00 Summary and closing words
... View more
Need help logging in or registering?
To create a new account, click the "Register" link in the upper right or just click here. The "Register" link opens in a new tab/browser window so that you can easily get back to the community after registering.
Here are some resources that may be of use:
What's my Community Display Name?
Cisco’s official help documentation for registration
Feel free to ask specific login or registration questions by replying to this thread; we’ll be happy to help!
//Nicklas Wägerth, NSO Developer Hub Community Lead
... View more