My trusty old heavily customized firewall-2.4-stronger script doesn't like systemd, so I think firewalld is probably the way to go, but it doesn't seem to support some of the things I need to do without resorting to direct rules, which seems to be undermining the whole "dynamic" idea. Maybe I missed something and there are better ways to do this. This is for a small office that I can't really replicate the setup of, so I can't test it properly without them being offline for a while. Maybe someone could tell me if I'm on the right track before I do that. There are three relevant ethernet interfaces: 0) cable modem in bridge mode (p35p1) - "external" zone 1) office lan (p2p1) - "work" zone - 192.168.10.0/24 segment 2) dmz for testing client machines (p3p1) - "dmz" zone 192.168.20.0/24 question 1 Internet traffic is being routed successfully from both internal networks out to the world and back. I used to have rules dropping packets between the two localnets, just to keep the customer machines from spreading viruses to the office. Even without those rules, the few tests I was able to try without their network to test on didn't connect. Did I miss something? Do I have to do something more to /enable/ routing between the two localnets? Or is this a fluke/misconfiguration/bad test I need to be concerned about? question 2 How exactly are zones applied? When a packet wants to be routed from the "work" localnet to the masquerading "external", which zone applies? Both of them? What if the packet is coming from an interface with one zone, from an address with another zone, routed to an interface with a third zone? How do zone rules translate to incoming, outgoing, and forwarding traffic? question 3 What are the recommended methods of blocking specific localnet addresses or the whole "work" zone from connecting to specific ports on external host ranges, i.e. no FaceBook at work? Would rich rules in the "work" zone be the proper way? It's kinda messy not being able to note the purpose of blocking a specific address when you have 20 or so different address ranges blocked and keep adding more. question 4 Is there a way to specify classes of destinations, like a destination zone? It would be nice to bundle up the ip ranges or even domains of FaceBook and Twitter and Tumblr and whatnot into a "SocialMedia" class and just block any traffic to those destinations, either from the "work" zone or from specific localnet IPs. Lists of IPs with no notes are pretty unwieldy and not very reliable. Although, the xml file does allow notes, so that's what I'm doing so far. It works, I think, but it's ugly. question 5 If I want to allow the dmz to only call out to the internet on specific services, like http/https, but no smtp or ftp, is it sufficient to just enable the services I want in the dmz zone? Does that affect connections that would just be masqueraded and forwarded out the external zone? What if I want to temporarily enable ftp from the dmz to one specific address, like a server on the work localnet? Would a rich rule for FTP service with an accept action do it? Would it have to be passive FTP only? That's a bit more question than I thought I had when I started writing this, but hopefully someone's still reading. Thanks in advance for any guidance you can offer. -- -Dave Noelle, dave(a)Straylight.org