Cisco Modeling Labs (CML) – A Packet Tracer Alternative for Network Practice

Throughout my career as a network engineer, I have used several network simulation tools such as Packet Tracer, GNS3, Eve-ng etc. Cisco Modeling Labs (CMS) emerged as probably the best option from all.

CMS offers a powerful platform for network simulation and design, providing tools for testing, troubleshooting, and learning network scenarios.

With its ability to simulate both Cisco and multi-vendor devices, it proves valuable for network engineers, architects and for professionals preparing for Cisco certifications.

This on-premises software accommodates different user needs, from personal to enterprise solutions. It can also serve as a better alternative to the well known Cisco Packet Tracer since it uses real IOS images so your lab modeling is as close to a real network as possible.

By using real IOS software you have all the commands and protocols available to configure just like a real networking device.

A strong community also supports Cisco Modeling Labs, with over 5,000 members contributing articles and tips. Engaging with this community can enhance learning and provide additional resources. More information about these offerings can be found through Cisco Modeling Labs and the DevNet platform.

Key Features

• Multi-vendor Support: It simulates networks from multiple vendors, making it a flexible choice for diverse environments.
• Compatibility: Users can build models with IOS-XE, NX-OS, IOS-XR, ASA, and even Linux nodes.
• Cost-effective Simulation: Fraction of the cost compared to physical labs, providing access to real VM images.
• Hands-on Learning: Offers a realistic environment for practicing configuration and troubleshooting, aiding in certification preparation.
• Supports Next Generation Firewall (NGFW): Provides access to Firepower Threat Defense virtual (FTDv) and Firepower Management Center virtual (FMCv).

Licensing Options and Cost

Cisco Modeling Labs offers several licensing options with different features and costs:

1. Free:

   There is a Free version of CML if you sign-up here. Not many people know about the Free version but you need to know its limited to only 5 running devices in the Lab simulation. However this can be a great option for CCNA practice or for other small network testing etc.

2. Personal:

   • Cost: $199 or 2 Cisco Learning Credits

   • Features:

     • Ships with 20 Cisco nodes

     • Community support only

     • Includes new features like smart annotations and NGFW access

3. Personal Plus:

   • Cost: $349 or 4 Cisco Learning Credits

   • Features:

     • Ships with 40 Cisco nodes

     • Community support only

     • Includes the same new features as the Personal version

4. Enterprise:

   • Features:

     • Ships with 20 Cisco nodes and can expand up to 300 nodes

     • Multi-user functionality

     • Community and TAC support

     • Includes features like LDAP improvements and custom MAC addresses.

5. Education:

   • Features:

     • Designed for educational institutions

     • Licensing per concurrent user instead of per node

     • Includes all new features and LDAP improvements

For pricing and additional details on Enterprise and Education versions, Cisco recommends contacting their sales team directly.

Which CML Version for CCNA, CCNP, CCIE

For CCNA Certification Prep.

For this path the Free CML might be enough if you already have some practical experience on Cisco devices and networks. I recommend to try first the free version and see if that’s enough for you, otherwise the Personal version will cover you fully for CCNA.

For CCNP Certification Prep.

Definitely you need the “CML Personal” license ($199) that allows you to have up to 20 running devices to test more complex networks and also run protocols like BGP etc.

For CCIE Certification Prep.

Here I suggest to get the “CML Personal Plus” license ($349) that allows you to have up to 40 running devices to test even more complex networks required for CCIE.

Overview of CML Deployment and Usage

The Cisco Modeling Labs (CML) installation guide outlines several deployment options:

1. Standalone vs. Cluster:

   • Standalone: Deploy a single instance of CML. Suitable for CML-Personal or CML-Personal Plus users.

   • Cluster: Available for non-personal products, allowing multiple instances with one acting as the controller. Enables horizontal scaling across multiple servers.

2. Bare Metal vs. Virtual Machine (VM):

   • VM Deployment: Often faster and easier to manage, using VMware. It employs nested virtualization for running network simulations.

   • Bare Metal: Requires a dedicated server, offering slightly better performance than VM deployments on equivalent hardware.

3. Cloud Deployment:

   • Supports AWS and Azure platforms, facilitated through a specialized toolchain in BETA. Specific instructions are available for each cloud platform.

4. In-Place Upgrades:

   • Allows upgrading from existing CML 2.x installations, applicable to both VM and bare metal deployments. Not all releases support in-place upgrades, and upgrades from CML 1.x to 2.x are not supported.

5. VM Images:

   • CML provides VM images for simulating nodes. It’s recommended to use the latest images for new installations, while existing installations can continue using older images post-upgrade.

CML Use Cases

By utilizing reliable models and reference platforms, users can design, test, and troubleshoot networks efficiently. Below, explore some of the main use cases in specific scenarios.

Certification Prep

CML is an essential tool for individuals preparing for network certification exams. Its ability to run network simulations helps users practice real-world scenarios, which is crucial for understanding and mastering complex networking concepts.

Candidates can use various Cisco and third-party device models, providing them with hands-on experience that is highly relevant to certification tests.

Teaching Network Classes

Educational institutions leverage CML to teach network classes effectively by providing students with a practical learning environment. Instructors use the platform to create custom labs and exercises that match the course curriculum.

Testing Network Configuration Before Deploying to Production

Before implementing configurations in live networks, network engineers use CML to test and validate their designs. This practice helps identify potential issues that might affect production environments, ensuring that networks function optimally when changes are deployed.

CML Vs Cisco Packet Tracer

Cisco Modeling Labs (CML) and Cisco Packet Tracer are both viable tools especially for certification practice and learning purposes.

The good old Cisco Packet Tracer is certainly a simpler and lighter option that does not require high system resources to run. However it is limited compared to CMS (in terms of the commands and features available) since it does not use real Cisco IOS images. It is sufficient for introductory learning such as CCNA preparation etc.

Cisco Modeling Labs on the other hand is designed for simulating real-world networks since it uses KVM as hypervisor to run real IOS network VM images. This requires a system with more resources (CPU, RAM) but provides a real-world experience.

Feature Comparison: