{"id":1658,"date":"2025-04-12T11:41:11","date_gmt":"2025-04-12T10:41:11","guid":{"rendered":"https:\/\/www.labtinker.net\/?p=1658"},"modified":"2025-04-12T11:41:11","modified_gmt":"2025-04-12T10:41:11","slug":"cisco-modelling-labs","status":"publish","type":"post","link":"http:\/\/18.135.13.153\/?p=1658","title":{"rendered":"Cisco Modelling Labs"},"content":{"rendered":"\n

I have been running up various labs for work, generally to test a feature or investigate a certain issue, and have found my desire to do any discretionary tinkering has decreased somewhat. When I’m not doing that I find I have to learn something new or occasionally relearn something old. (I think I have now forgotten more than I know)<\/p>\n\n\n\n

To this end, I recently started working through a Cisco ENCOR 350-401 course with no intention of taking the exam, but just to brush up on some networking fundamentals:<\/p>\n\n\n\n

https:\/\/www.udemy.com\/course\/cisco-encor\/<\/a>. <\/p>\n\n\n\n

It is a very good course and I recommend it. It also has labs which come in the form of yaml files you can import into Cisco Modelling Labs (CML). I didn’t have CML but there was a sale on so I decided to make the investment (which is fairly substantial: $200-ish) and give it a go.<\/p>\n\n\n\n

I had tried it in a previous incarnation when it was VIRL and I gave up on that when I realised I was spending more time troubleshooting VIRL than I was learning networking. The updated product is much improved.<\/p>\n\n\n\n

You install CML as a VM with an attached refplat ISO ‘disk’ which contains all the network images you need and this can be downloaded from the same place you get the CML download. I don’t remember this requirement being especially clear (though I can be guilty of skimming installation instructions). However, here I would read them carefully, make sure you have the ISO disk attached to your VM and modify your VM’s settings in line with the given recommendations before starting it.<\/p>\n\n\n\n

Also I found Nexus switches don’t work on the ‘gold star’ 2.7 CML version (you get no console) but do work on the cutting edge 2.8 version. Also you need a fairly beefy machine – I have a NUC with 64GB of RAM and VMware Workstation Pro 16. (Apparently, this is now free for personal use)<\/p>\n\n\n\n

What I liked about CML is that my original use-case did actually work: I imported the yaml files from the course and had a lab up and ready. I am always surprised when something actually works as advertised! Also, the labs seemed to start reasonably quickly – though the Nexus behemoths take a while go come up. I did try Nexus switches on GNS3 but never really got them stable and I needed to lab with these so I guess that was another use-case. Another advantage with CML is you get all the Cisco images:<\/p>\n\n\n\n

https:\/\/developer.cisco.com\/docs\/modeling-labs\/vm-images-for-cml-labs<\/a><\/p>\n\n\n\n

…which is obviously not the case with GNS3 or EVE-NG. The CML GUI (which is accessed through a browser) was pretty intuitive and easy to pick up.<\/p>\n\n\n\n

Disadvantages are I guess that is not designed to integrate with non-Cisco images. It’s probably possible but I can’t see it being as easy as in GNS3, and it is an investment.<\/p>\n\n\n\n

I think my CML VM is going to get a fair bit of use…after years spent at Layer 3 \/ 4 with firewalls, proxies, and WAFs, circumstance find me playing with Nexus switches and trying to get my head round vPC. I will possibly post on this later for any die-hard readers eager for a proper lab-based post.<\/p>\n","protected":false},"excerpt":{"rendered":"

I have been running up various labs for work, generally to test a feature or investigate a certain issue, and have found my desire to do any discretionary tinkering has decreased somewhat. When I’m not doing that I find I have to learn something new or occasionally relearn something old. (I think I have now […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[8],"tags":[],"class_list":["post-1658","post","type-post","status-publish","format-standard","hentry","category-general"],"jetpack_featured_media_url":"","_links":{"self":[{"href":"http:\/\/18.135.13.153\/index.php?rest_route=\/wp\/v2\/posts\/1658","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/18.135.13.153\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/18.135.13.153\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/18.135.13.153\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/18.135.13.153\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1658"}],"version-history":[{"count":0,"href":"http:\/\/18.135.13.153\/index.php?rest_route=\/wp\/v2\/posts\/1658\/revisions"}],"wp:attachment":[{"href":"http:\/\/18.135.13.153\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1658"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/18.135.13.153\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1658"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/18.135.13.153\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1658"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}