Still celebrating National IT Professionals Day with 3 months of free Premium Membership. Use Code ITDAY17

x
?
Solved

Cisco 12.2(1b)

Posted on 2004-04-26
3
Medium Priority
?
256 Views
Last Modified: 2010-04-11
Current Setup:
ISP ------>Cisco2514----->LAN

1) My ISP NATS my public ip to 10.20.20.100
2) Cisco2514 NAT/PAT to 172.16.8.0/24
3) So the computers in my LAN get NATed twice.
4) I do PAT for www, mail, dns, etc...

WHAT I WANT TO DO, is this:
ISP ------>Cisco2514----->Firewall---->LAN

1) How do I get my Cisco2514 to pass all packets to the firewall?
0
Comment
Question by:mesican
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 2
3 Comments
 
LVL 11

Expert Comment

by:PennGwyn
ID: 10923743
Assign the LAN side interface of the firewall the gateway address that the clients use (currently on LAN side of 2514).

Assign the other side interface of the firewall an address in a different private range, say 172.16.124.2/24

Change the address of the LAN side interface of the 2514 to be in the same range, say 172.16.124.1/24

Give the 2514 a route telling it that your LAN is on the other side of the firewall:

ip route 172.16.8.0 255.255.255.0 172.16.124.2

Tell the firewall to use the 2514 (172.16.124.1) as its default gateway/route.

0
 

Author Comment

by:mesican
ID: 10923825
So packets that come in not destined for the lan will still get sent to the lan side?
0
 
LVL 11

Accepted Solution

by:
PennGwyn earned 200 total points
ID: 10932292
Packets that come in destined for the LAN will get forwarded to the firewall.  Packets that come in for anywhere else (there shouldn't be any, but...) will get sent to the router's default route/gateway, which still points back to the Internet so that packets *from* the LAN can get there.  (If the ISP insists on delivering packetes that aren't for you, they'll bounce between you and the ISP until they run out of TTL.)

0

Featured Post

How to Use the Help Bell

Need to boost the visibility of your question for solutions? Use the Experts Exchange Help Bell to confirm priority levels and contact subject-matter experts for question attention.  Check out this how-to article for more information.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

If you’re involved with your company’s wide area network (WAN), you’ve probably heard about SD-WANs. They’re the “boy wonder” of networking, ostensibly allowing companies to replace expensive MPLS lines with low-cost Internet access. But, are they …
This article explains the fundamentals of industrial networking which ultimately is the backbone network which is providing communications for process devices like robots and other not so interesting stuff.
In this tutorial you'll learn about bandwidth monitoring with flows and packet sniffing with our network monitoring solution PRTG Network Monitor (https://www.paessler.com/prtg). If you're interested in additional methods for monitoring bandwidt…
In this brief tutorial Pawel from AdRem Software explains how you can quickly find out which services are running on your network, or what are the IP addresses of servers responsible for each service. Software used is freeware NetCrunch Tools (https…
Suggested Courses

715 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question