3

I am trying to deploy a set of advanced windows firewall ACLs to several 2008 R2 servers. I would like to (i have to) ensure that no local or old rules are getting applied.

So I set "Apply local firewall rules" to "No" within each profile (GPO). This does only apply to local firewall rule merging (as the name implies). Different rules which are getting set by other GPOs are additive and sum up. This makes sense if I think about it.

However this is a problem as through experimenting things became messy on my test machines. So I created another GPO calling a script that deletes all firewall rules in advance (netsh advfirewall firewall delete rule name=all), which leads to a corruptive file and printer sharing service.

So to cut it short: What is be the best/recommended way to ensure a clean rule base before applying new ones?

3
  • Are you wanting to ensure your test machines remain free of other GPO firewall settings (for testing purposes), or do you want this to apply to production server as well? Feb 19, 2014 at 11:39
  • I think my question was not clear enough. The firewall is configured (GPO) to not apply local firewall or connection security rules. But it does. And it also breaks the file and printer sharing service (serverfault.com/questions/576438/…) Feb 19, 2014 at 13:21
  • When i export a default firewall ruleset from a reference server and import it back into a gpo it corrupts the service... Feb 19, 2014 at 13:31

1 Answer 1

2

You said the local firewall rules are applied regardless of the "do not apply local rules" gpo setting. Just to confirm, the local firewall rule will still be present in the "\inbound rules, \outbound rules" sets however you can see the actual "effective" policies (local + gpo) by viewing the "\monitoring\firewall" node.

If you are having conflicting firewall rules across gpo's in your OU structure there isn't much the windows firewall portion is going to help you with. You could do things like change your ou structure, use security filtering per machine, or block inheritance. Overall though your policies would probably setup best by adding more general gpo/fw settings higher in the ou structure and more specific gpo/fw settings directly on the servers ou.

1
  • Finding how to see the "effective" firewall after GPO was really frustrating me, but it was so obvious. Thank you for the answer! Apr 5, 2023 at 0:11

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .