Velocity Reviews - Computer Hardware Reviews

Velocity Reviews > Newsgroups > Computing > Cisco > Port forwarding on Cisco 837

Reply
Thread Tools

Port forwarding on Cisco 837

 
 
Danny Horne
Guest
Posts: n/a
 
      11-20-2004
Hi all,

I'm trying to configure port forwarding on a Cisco 837 router from
varying external IP's to IP's on 192.168.46.0/24

I've googled this group for answers to my question & have come to the
conclusion that all I need (for example) is -
ip nat inside source static tcp <internal IP> 21 <external IP> 21
extendable

But would this actually open up the required ports on the external
interface or is something like -
access-list 101 permit tcp any host <external IP> eq 21
and on the external interface -
ip access-group 101 in
required?

Thanks for all replies
 
Reply With Quote
 
 
 
 
PES
Guest
Posts: n/a
 
      11-20-2004
Danny Horne wrote:
> Hi all,
>
> I'm trying to configure port forwarding on a Cisco 837 router from
> varying external IP's to IP's on 192.168.46.0/24
>
> I've googled this group for answers to my question & have come to the
> conclusion that all I need (for example) is -
> ip nat inside source static tcp <internal IP> 21 <external IP> 21
> extendable


This is correct for the nat translation creation and is always required
if you are doing PAT.

> But would this actually open up the required ports on the external
> interface or is something like -
> access-list 101 permit tcp any host <external IP> eq 21
> and on the external interface -
> ip access-group 101 in
> required?


If there is no access-list (you should find an ip access-group command
on the interface), all traffic is permitted. If there is an access list
applied, the access-list must be modified as you indicated above. Your
syntax is correct. However, make sure that you understand that the ACL
is processed from the top down and has an implicit deny any any at the
bottom (regardless of its exitstence in the config).


--
-------------------------
Paul Stewart
Lexnet Inc.
Email address is in ROT13
 
Reply With Quote
 
 
 
Reply

Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Cisco 837 VPN Port forwarding uanmi Cisco 0 05-18-2007 03:41 PM
VPN between Cisco 837 and cisco 837 with IP static and ip dinamic lyvicro@hotmail.com Cisco 4 12-15-2005 09:10 PM
Cisco 837 VPN, NAT and Port Forwarding Weili Cisco 2 03-01-2005 01:14 AM
Port forwarding with Cisco 837 Doc Oakenfold Cisco 4 01-28-2005 07:54 PM
Cisco 837 to Cisco 837 VPN, ping OK, NetBios / VNC DROPPING! Suppa Lamah Cisco 8 12-19-2003 01:15 PM



Advertisments