One of the most common questions about building out a CCNA lab I’ve seen on the internet is should I buy equipment and start a physical lab, or should I use Packet Tracer to study for the CCNA. There have been videos from many Youtubers covering this and it generally comes down to two points of view. I’ll be discussing both of those here.
Option 1: Packet Tracer/GNS3
Packet Tracer is a powerful tool, and for many, the only tool needed to lab out the CCNA. It includes simulators for routers, switches, wireless access points and more. In fact, this is the software that Cisco recommends for getting started with the CCNA. Oh and did I mention, Packet tracer is free. The downsides to Packet Tracer is that it won’t be very helpful outside the CCNA, the simulators are not full Cisco IOS simulators and have a limited set of available commands and configurations that can be tested.
Packet Tracer is great when you need to test a quick setup that falls within its limited range of available commands and configurations. This is its biggest weakness in my opinion. I don’t think that the knowledge burns in as deep when using simple tools like Packet Tracer, there’s something special about using real IOS images and having the full power of a real Cisco image as they react the same as any Cisco device will in the field.
GNS3 is another powerful tool that allows complex network layouts and can simulate more than just Cisco equipment. GNS3 is used by many major companies to lab out complex network environments that have equipment from multiple vendors. GNS3 supports full Cisco IOS images and can emulate many Cisco devices. GNS3 also works well beyond the CCNA and can be used for studying for the CCNP and beyond. Sounds great, right? Not so fast. In order to use GNS3 you need to collect an image for each of the devices you want to use in your virtual lab. There aren’t many ways to legally obtain these images, you can either have a support contract from Cisco or get a VIRL subscription. This leaves GNS3 out of the options for me. Even after getting GNS3 up and running and stable you can come across a bunch of issues just by updating the software, I’ve had GNS3 break after an update and was unable to get some of my router images working again.
Option 2: Physical Lab
Physical Labs are fantastic for learning because they give you a real hands on experience with equipment. A lot of network engineers may not actually work hands on with equipment very often, we generally spend most of our time working on equipment remotely from our desk. Lab time is a great time to actually work hands on with equipment. Having actual equipment is also great because you learn what interfaces are compatible and for those who don’t already have a lot of networking experience, what the cabling looks like and how it interacts. I’ve made cabling mistakes before and having experienced those issues with real equipment, I was able to troubleshoot much faster and resolve those issues much faster. For me, physical labs are the gold standard.
The downside to physical labs are many, they’re big, heavy, loud and can be very power hungry depending on what you have in your lab. For many, this is enough to keep them from building out a physical lab.
I plan to write up a guide on building out a physical Cisco lab in the future.
Option 3: Hybrid Lab
Hybrid Labs can solve some of these issues for those who want to take the time to make it work. Hybrid labs means running some physical gear and some virtual gear. I’ve tested out running GNS3 with a Cisco 2821 and it worked out well, I created a bridged subnet for my GNS3 lab and physical lab, I was able to make this work out okay, however this can be difficult when needing to construct a more complicated setup for routing labs. I don’t recommend this unless you know what you’re doing already and have a bit of networking experience.
In summary, there are some great tools for getting started with CCNA labs, many can be had for free or very cheap. I would also check with your employer, you may have access to Cisco VIRL or similar tools. I would choose whatever will get you studying and falls within your price range.