Monarx

Pros: The one thing I can say is that it definitely protects you. From threats, legitimate users, traffic, uploads, and apparently anything else that happens to interact with the server.

Cons: Monarx seems to follow a very simple security philosophy: if something moves, makes noise, uploads a file, or looks remotely suspicious, block it.

It blocks legitimate activity constantly and can remove files from the server without any meaningful notice.

Getting something unblocked is another adventure. I have to contact an administrator, who then has to submit another request somewhere higher up the chain. By the time the issue is resolved, the traffic or customer is already gone.

We have lost a significant amount of legitimate traffic because of this.

Overall: Security is supposed to distinguish between malicious and legitimate activity. Blocking everything is not security; it is just shutting the door and throwing away the key.

From what I can see, Monarx relies in part on AbuseIPDB data. I checked many of the IP addresses that were blocked. A lot of them had only 1–5 reports, with some reports more than a year old, and threat/confidence scores of 0%.

Still blocked.

Trying to upload a file? Blocked.

Legitimate traffic? Blocked.

Anything slightly unusual? Blocked.

At this point, the safest way to use the server would probably be not to use it at all.

Creating security software is not about blocking everything. The difficult part is blocking actual threats while allowing legitimate users and applications to function.