🚫 One Palo Alto Firewall Mistake I See in Almost Every Network

Most teams focus heavily on allow rules.
Very few spend time designing deny logic properly.

And that’s where problems start.
🔍 What usually happens
Policies are written as:
Source: Any | Destination: Any | App: Any | Service: Any
Security profiles are added and teams feel “protected”
Logs are noisy, investigations are slow, and breaches go unnoticed

🧠 Architect mindset (not engineer mindset) A firewall is not just a packet filter.
It’s a policy enforcement point.
That means:
Zones must tell a story
Rules must reflect intent
Deny rules must be explicit, logged, and reviewed

✅ What I recommend
Always place explicit deny rules at the bottom
Enable logging on denies (this is your free IDS)
Never use any-any-any in production unless it’s temporary
Use Palo Alto App-ID to describe traffic, not ports
Review deny logs weekly — patterns reveal misdesign

🔥 Final thought Good security isn’t about adding more rules.
It’s about removing ambiguity.
If your firewall policy needs tribal knowledge to understand,
it’s already broken.