Running Arista cEOS in GitHub Codespaces
Yesterday, I explained how you can run netlab examples in GitHub codespaces and mentioned that they work best with vendors who understand the value of frictionless downloads. But what if you’d like to use a device from one of the good guys who provide the container images but require a registration?
It turns out the solution is trivial:
Running Arista cEOS in GitHub Codespaces
Yesterday, I explained how you can run netlab examples in GitHub codespaces and mentioned that they work best with vendors who understand the value of frictionless downloads. But what if you’d like to use a device from one of the good guys who provide the container images but require a registration?
It turns out the solution is trivial:
Netlab Examples in GitHub Codespaces
A few days ago, someone asked me about the IPv4 next-hop details of running interface EBGP sessions. I pointed him to a blog post explaining them, adding, “And of course, you can test that in netlab.” A few minutes later, it hit me: instead of asking him to set up netlab locally, I could enable him to do that in a minute with GitHub codespaces.
Setting that up was easy: copy the .devcontainer directory from the BGP labs repository into the netlab examples repository and commit the change. After a short yak-shaving exercise (writing README files and rearranging a few folders), I successfully started the codespace and was ready for this blog post. There was just one gotcha…
Netlab Examples in GitHub Codespaces
A few days ago, someone asked me about the IPv4 next-hop details of running interface EBGP sessions. I pointed him to a blog post explaining them, adding, “And of course, you can test that in netlab.” A few minutes later, it hit me: instead of asking him to set up netlab locally, I could enable him to do that in a minute with GitHub codespaces.
Setting that up was easy: copy the .devcontainer directory from the BGP labs repository into the netlab examples repository and commit the change. After a short yak-shaving exercise (writing README files and rearranging a few folders), I successfully started the codespace and was ready for this blog post. There was just one gotcha…
Worth Reading: The Evolution of Network Security
Sharada Yeluri published an interesting overview of the evolution of network security, from packet filtering firewalls to GenAI and Quantum Computing (yeah, she works for a networking vendor ;). Definitely worth reading if you’re looking for an intro-level overview.
Worth Reading: The Evolution of Network Security
Sharada Yeluri published an interesting overview of the evolution of network security, from packet filtering firewalls to GenAI and Quantum Computing (yeah, she works for a networking vendor ;). Definitely worth reading if you’re looking for an intro-level overview.
Worth Reading: Don’t Use Excel as a Source of Truth
Some people insist on using Excel as the ultimate source of user-supplied data (including network automation source of truth).
If you agree with me that that’s not necessarily the best idea out there, you might enjoy this rant by Nikhil Suresh.
Worth Reading: Don’t Use Excel as a Source of Truth
Some people insist on using Excel as the ultimate source of user-supplied data (including network automation source of truth).
If you agree with me that that’s not necessarily the best idea out there, you might enjoy this rant by Nikhil Suresh.
Explore and Fix BGP Wedgies
RFC 4264 defines BGP wedgies as “a class of BGP configurations for which there is more than one potential outcome, and where forwarding states other than the intended state are equally stable.” Even worse, “the stable state where BGP converges may be selected by BGP in a non-deterministic manner.”
Want to know more? You can explore a real-life BGP wedgie and fix it in the latest BGP lab exercise.
Explore and Fix BGP Wedgies
RFC 4264 defines BGP wedgies as “a class of BGP configurations for which there is more than one potential outcome, and where forwarding states other than the intended state are equally stable.” Even worse, “the stable state where BGP converges may be selected by BGP in a non-deterministic manner.”
Want to know more? You can explore a real-life BGP wedgie and fix it in the latest BGP lab exercise.
Looking for a Simple Multihop EBGP Use Case
I plan to add several challenge labs using multihop EBGP sessions to the BGP labs project, including:
- Running BGP between VMs and central BGP route servers
- Using multihop EBGP session to send full Internet routing table to a customer without overloading the PE-router
- Running EBGP EVPN session between loopbacks advertised with EBGP IPv4 session (🤢)
However, I would love to start with a simple use case to help engineers unfamiliar with BGP realize when they might have to use multihop EBGP sessions. Unfortunately, I can’t find one, and the scenarios where I used multihop EBGP in the past (EBGP load balancing and using a low-end router in the EBGP path, where I was effectively using the reverse application of #2 as a customer) are mostly irrelevant.
Would you have an easy-to-understand use case that is best solved with a multihop EBGP session? Please share it in the comments. Thanks a million!
Looking for a Simple Multihop EBGP Use Case
I plan to add several challenge labs using multihop EBGP sessions to the BGP labs project, including:
- Running BGP between VMs and central BGP route servers
- Using multihop EBGP session to send full Internet routing table to a customer without overloading the PE-router
- Running EBGP EVPN session between loopbacks advertised with EBGP IPv4 session (🤢)
However, I would love to start with a simple use case to help engineers unfamiliar with BGP realize when they might have to use multihop EBGP sessions. Unfortunately, I can’t find one, and the scenarios where I used multihop EBGP in the past (EBGP load balancing and using a low-end router in the EBGP path, where I was effectively using the reverse application of #2 as a customer) are mostly irrelevant.
Would you have an easy-to-understand use case that is best solved with a multihop EBGP session? Please share it in the comments. Thanks a million!
Running BGP Labs in GitHub Codespaces
I love open-source tools (and their GitHub repositories). Someone launches a cool idea, and you can dig through their source code to figure out how it works. It beats reading documentation or fixing AI hallucinations every day of the week ;)
Not too long ago, the containerlab team launched the ability to run containerlab within a free1 container2 running on GitHub, and that seemed like a perfect solution to run the BGP labs (Jeroen van Bemmel pointing me in the right direction was another significant step forward).
Running BGP Labs in GitHub Codespaces
I love open-source tools (and their GitHub repositories). Someone launches a cool idea, and you can dig through their source code to figure out how it works. It beats reading documentation or fixing AI hallucinations every day of the week ;)
Not too long ago, the containerlab team launched the ability to run containerlab within a free1 container2 running on GitHub, and that seemed like a perfect solution to run the BGP labs (Jeroen van Bemmel pointing me in the right direction was another significant step forward).
netlab 1.8.4: vrnetlab Containers, Catalyst 8000v
I don’t think I ever created two netlab releases in a week, but last week, I stumbled upon a motherlode of goodies, and it would be a shame not to make them available.
Someone tried to use netlab with vrnetlab containers for CSR 1000v and Nexus 9300v. We got it to work, but when I started integrating his changes into the development branch, I wanted to test them, so I installed vrnetlab to create my own container images. vrnetlab is an excellent tool, and building containers is a breeze (running them is a different story), so I added support for vrnetlab containers for every device supported by that tool and netlab for which I happened to have a disk image.
netlab 1.8.4: vrnetlab Containers, Catalyst 8000v
I don’t think I ever created two netlab releases in a week, but last week, I stumbled upon a motherlode of goodies, and it would be a shame not to make them available.
Someone tried to use netlab with vrnetlab containers for CSR 1000v and Nexus 9300v. We got it to work, but when I started integrating his changes into the development branch, I wanted to test them, so I installed vrnetlab to create my own container images. vrnetlab is an excellent tool, and building containers is a breeze (running them is a different story), so I added support for vrnetlab containers for every device supported by that tool and netlab for which I happened to have a disk image.
Worth Reading: You Probably Don’t Need AI
Here’s another rant to spice up your weekend: focus on fixing your company’s problems instead of chanting the AI mantra. Have fun ;)
Worth Reading: You Probably Don’t Need AI
Here’s another rant to spice up your weekend: focus on fixing your company’s problems instead of chanting the AI mantra. Have fun ;)
Automated Validation of BGP Labs
In late 2023, I started playing with the idea of having automated validation in netlab. The early implementation was used in BGP labs, and a user liked it so much that he opened an issue saying:
I would suggest providing netlab validate for each lab.
Numerous rounds of yak-shaving later, I merged a humongous commit that adds automated validation to these lab exercises:
Automated Validation of BGP Labs
In late 2023, I started playing with the idea of having automated validation in netlab. The early implementation was used in BGP labs, and a user liked it so much that he opened an issue saying:
I would suggest providing netlab validate for each lab.
Numerous rounds of yak-shaving later, I merged a humongous commit that adds automated validation to these lab exercises: