Cisco Setup: ROMMON Upgrade, ASDM Refresh & Multi-Context Magic

This week at Null0 Labs, we go hands-on with a real Cisco ASA 5516-X—prepping it for a future project by upgrading the ROMMON, ASA software, and ASDM. Then we dive deep into multi-context mode, turning one physical firewall into two fully isolated virtual firewalls.

What’s covered:
• ROMMON upgrade for bootloader stability
• ASA software & ASDM refresh for modern features
• Multi-context mode configuration
• Context separation: interfaces, NAT, policies
• Real hardware getting ready for deployment

💡 Multi-context mode lets you carve up a single ASA into multiple logical firewalls—perfect for multi-tenant environments or lab segmentation. It’s not just theory—we show it working on real gear.

0:00 Intro
4:05 Device firmware upgrade
11:00 Multi Context Setup
42:15 Outro

🛠️ Stuff I Use 🛠️
EVE-NG - multivendor network emulation software.
Linux, Ubuntu, Debian
OSX, Windows
Networking hardware - Multi vendor

👨🏻‍💻 About Me:
Hi I'm Matt a Senior Network Engineer with over two decades of hands-on experience architecting, securing, and optimising high-availability networks across enterprise environments. I stream labs and create video content to help others level up their skills.


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Website: [null0labs.com](https://null0labs.com)
GitHub: [@null0labs](https://github.com/null0labs)
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LinkedIn:[@mlewisonline](  / mlewisonline  )


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