|
||||||||||
Thanks... I have already setup a page in the wiki "FirewallBehindRouter". I plan on showing sanitized Border Router config as well as m0n0wall. As I get this worked out I will post my steps. For me, it will server as self documentation as well as contributing to the project. On Sat, 5 Mar 2005 00:23:24 -0500, Chris Buechler <cbuechler at gmail dot com> wrote: > On Fri, 4 Mar 2005 14:20:21 -0500, Don Munyak <don dot munyak at gmail dot com> wrote: > > I am still trying to work through this so if something doesn't make > > sense, it's either because I'm not sure or I didn't do a good job of > > explaining it. > > > > SCENARIO: > > I would like to use introduce m0n0wall into our network as a second > > layer of physical defense. We have a group of public servers, web and > > email. We have a public subnet range of 14 useable IP's. We are not > > using all of them currently. > > > > Existing public access is gained by NAT'ing Public IP's to > > non-routeable Private IP's for a given server and limiting the > > Protocol used for public access. Once I figure out some of the pieces > > I need to forward inbound requests, I will probably re-work the > > existing ACL's. > > > > The Cisco Border Router is configured as such: > > > > >>> EXISTING Config: > > > > --Internet-----(s0.744)Router/FW(e0)-----LAN > > > > s0.744 > > xx.43.154.230 / 255.255.255.252 > > > > e0 > > xx.43.155.33 / 255.255.255.240 > > 192.168.222.1 / 255.255.255.0 secondary > > > > ip nat inside source static 192.168.222.18 xx.43.155.45 > > ip nat inside source static 192.168.222.2 xx.43.155.43 > > ip nat inside source static 192.168.222.40 xx.43.155.41 > > ip nat inside source static 192.168.222.9 xx.43.155.39 > > > > -- REMARK Reflexive ACL applied to s0 interface > > ip access-list extended InboundFilters > > permit tcp any host xx.43.155.45 eq smtp > > permit tcp any host xx.43.155.45 eq pop3 > > permit tcp any host xx.43.155.45 eq 32000 > > etc... > > > > Where I'd like to go. > > >>> NEW Config: > > --Internet-----(s0.744)Router(e0)-----(e1)Firewall(e0)-----LAN > > > > Router (s0.744) x.43.154.230 > > Router (e0) x.43.155.33 > > > > Firewall (e1) x.43.155.46 (???) > > Firewall (e0) 192.168.222.1 > > > > GOALS: > > - Need to route incoming requests to public servers behind firewall. > > - NAT overload question. currently, the LAN uses a NAT overload > > (sharing one Public IP) for outbound traffic. > > - Allow outbound only passive ftp from LAN hosts to remote FTP servers > > > > QUESTIONS: > > 1. I am not sure how to route specific IPs to the LAN side of m0n0wall. > > 2. How would you configure the router to forward requests for hosts on > > the subnet. > > Take out the IP NAT statements. Take off the private IP on the > router. You can take out the ACL or leave it, just make sure it > matches up appropriately with firewall rules. For ease of > troubleshooting (no questioning if it's the router or the firewall), > at least during the setup, take it out. You can add it back later > after things are working with the new setup as another line of defense > if you want. It's not necessary though. > > > > 3. I am very confused by 1:1 vs NAT Server > > 1:1 means translating one public IP to one private IP, on both inbound > and outbound traffic. Server NAT differs in that it allows you to > open multiple ports on one public IP to different LAN side hosts. > Inbound NAT does the same thing, but uses the m0n0wall WAN IP. Server > NAT lets you use public IP's other than the WAN, which is what your > LAN hosts other than any with 1:1 setups will be NAT'ed to outgoing. > > Since you have 14 public IP's, I'd use 1:1 NAT because it's more > flexible, and easier to understand IMO. It's easier to mentally > picture IP x.x.x.3 goes to mail server, x.x.x.4 is web server, x.x.x.5 > is ..., etc. rather than what port goes where on a single IP (which is > how you have it set up now) > > > > This is a real business project for me. I would be glad to help create > > a real-world "HOW-TO" for the documentation project. My particular > > topology I would assume is pretty common for small businesses. > > > > This would be good for the example configurations chapter. > http://m0n0.ch/wall/docbook/examples.html > > If you write something up (the wiki would be a good place, > http://wiki.m0n0.ch), I can add the network diagrams, screenshots, and > format it in DocBook for the docs. > > -Chris > |