Looking for Free or Open-Source Patch Management Tools

If you have under 200 devices, Action1 could be a great choice. For a larger setup like yours, though, you might want to consider PDQ Deploy, which has a solid free tier for Windows. If you're leaning more towards Linux, a combination of Ansible and cron jobs could work well, but it does require some upfront setup. ManageEngine's Patch Manager Plus also has a free version for up to 25 devices, but that won't cover your needs. What do you think about the mix of Linux and Windows? That could influence your choice.

Tactical RMM has its issues, but I’ve found it pretty solid overall. Just keep in mind there was some drama about a crypto miner in a repo related to it, which made folks wary. Another option to look into is the Comodo tool—it's technically "free" as you get credits back each month, but it might not be the best if you're used to completely free tools. Just sharing my experience here!

Looking for a free patch management solution for 400 endpoints might be a bit tricky. PDQ could be your best bet, but for a more robust solution, I’d really recommend checking out licensed products like ManageEngine. They might save you headaches in the long run.