?
Solved

Cisco 1720 Router

Posted on 2005-03-04
5
Medium Priority
?
443 Views
Last Modified: 2013-11-29
I am never set up a Cisco router from scratch before.  I have both ethernet ports setup one with a local lan ip & the other with a public ip. When I telnet into the router, I can ping www.google.com with success.  If I set my pc to use the router as a gateway & ping google from a command prompt, it returns my routers lan ip as responding. Any clues as to what might be wrong??

Thanks in advance!
0
Comment
Question by:8lackd0g
[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
  • 2
5 Comments
 
LVL 10

Expert Comment

by:plemieux72
ID: 13463977
Can you post your router config?  Also, please advise if when ping a public IP address like 198.133.219.25 from your PC you get a reply.
0
 
LVL 15

Accepted Solution

by:
getzjd earned 1000 total points
ID: 13463995
You need a default Route  and NAT/PAT
For default route

Ip Route 0.0.0.0 0.0.0.0 S0  

 Assuming S0 is your internet connection.

You will also need to configure PAT
Router#conf t

Enter configuration commands, one per line.  End with CNTL/Z.

Router(config)#interface ethernet0

Router(config-if)#ip nat inside

Router(config-if)#interface serial0

Router(config-if)#ip nat outside



Router(config)#ip nat inside source list 1 interface serial0 overload

Router(config)#access-list 1 permit 192.168.1.0 0.0.0.255   *** change this to suit your IP scheme to permit your network to access the interface

That should get you going.



If you have any other questions about configuring, you may want to post your config.. just makes sure to XXXX out your passwords .
0
 

Author Comment

by:8lackd0g
ID: 13464174
Thanks!! I added your two last suggestions & it works perfectly!

Router(config)#ip nat inside source list 1 interface ethernet0 overload

Router(config)#access-list 1 permit 192.168.1.0 0.0.0.255

I also have a few entries that I have not seen before:

ip virtual-reassembly
no cdp enable (if I try to enable, I get an error "service not running")
no service password-encryption (does this hide my router password?)

Should this be changed? -- snmp-server community public RO

Nice router for $300 bucks.  Came with 12.3, WIC Fast Ethernet & more memory than the 1721!
0
 
LVL 15

Expert Comment

by:getzjd
ID: 13464212
If i were you I would issue the command
Service password-encryption  to encrypt your passwords.  

This link here will explain what the CDP means

http://www.cisco.com/en/US/products/sw/iosswrel/ps1831/products_configuration_guide_chapter09186a00800ca66d.html

The SNMP community can be changed to your liking, however you will probably never use it.  You can use SNMP to do things like monitor utilization of your interfaces from your desktop etc.

Here is an app that can do such a thing http://www.paessler.com/prtg


Virtual-Reassembly or VFR  can be used to  help against some types of attacks.  Rather than reinvent the wheel and type out a long description, I will let cisco do the explaining :)  

http://www.cisco.com/univercd/cc/td/doc/product/software/ios123/123newft/123t/123t_8/gt_vfrag.htm
0
 

Author Comment

by:8lackd0g
ID: 13465732
Dam! Wish I could have increase the points awarded. Thank you very much!
0

Featured Post

NEW Veeam Agent for Microsoft Windows

Backup and recover physical and cloud-based servers and workstations, as well as endpoint devices that belong to remote users. Avoid downtime and data loss quickly and easily for Windows-based physical or public cloud-based workloads!

Question has a verified solution.

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

Short answer to this question: there is no effective WiFi manager in iOS devices as seen in Windows WiFi or Macbook OSx WiFi management, but this article will try and provide some amicable solutions to better suite your needs.
A 2007 NCSA Cyber Security survey revealed that a mere 4% of the population has a full understanding of firewalls. As business owner, you should be part of that 4% that has a full understanding.
Get a first impression of how PRTG looks and learn how it works.   This video is a short introduction to PRTG, as an initial overview or as a quick start for new PRTG users.
This video gives you a great overview about bandwidth monitoring with SNMP and WMI with our network monitoring solution PRTG Network Monitor (https://www.paessler.com/prtg). If you're looking for how to monitor bandwidth using netflow or packet s…
Suggested Courses
Course of the Month11 days, 20 hours left to enroll

752 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