Help with arguments for Open Source/Freeware (like LibreNMS)

I'm having problems making a business case for using LibreNMS with Oxidized at my company. I'm also looking at Eve-NG for us.

I've installed and presented the application and it's uses. It's ease of integration with our environment, and I found it much easier to set up than solarwinds or OpManager (who dont support our network switches by default). I set up a test environment and it is working wonderfully.

But I'm always met with the same questions

• Isn't opensource less secure?

• Can we buy support?

• Isn't freeware less reliable?

Even with examples like SolarWinds getting breached, they'd prefer to spend on a purchasable product as they are deemed more reliable and secure, going through RFP and RFQ processes to multiple vendors.

For the Support argument, they want to have professional support for any system or application so the accountability can be shifted in emergency. We've always found professional services very lacking, but still get them.

I can easily just do all of this work under the radar, and have full monitoring and configuration management with whatever utilities I want without anyone knowing (until I get audited), but I'd rather have the business know and approve.

I'm one guy servicing 500 switches, 200 wireless access points, over a 10km campus, and I'm tired of doing everything manually without any visibility, I jsut need to make a good argument for tools I think would best help us.