From: Brian Dennis (bdennis@internetworkexpert.com)
Date: Wed Aug 11 2004 - 15:25:34 GMT-3
<Qoute>
At the first glance I would say that this example would translate source
address whit IP 172.16.0.2 to 224.0.0.9 when the packet goes from
outside to inside; ok, it would really does it if there was a response
for RIP updates, which is not the case.
</Quote>
The source IP address of a packet is never multicast. The translation
is changing the normal RIPv2 destination address of 224.0.0.9 to the
unicast address of 172.16.0.2.
The logic of the command is:
ip nat outside source static <global-ip> <local-ip>
In this case the original destination IP address of 224.0.0.9 (local-ip)
is NAT'ed to 172.16.0.2 (global-ip).
Brian Dennis, CCIE #2210 (R&S/ISP-Dial/Security)
bdennis@internetworkexpert.com
Internetwork Expert, Inc.
http://www.InternetworkExpert.com
Toll Free: 877-224-8987
Direct: 775-745-6404 (Outside the US and Canada)
-----Original Message-----
From: nobody@groupstudy.com [mailto:nobody@groupstudy.com] On Behalf Of
gladston@br.ibm.com
Sent: Wednesday, August 11, 2004 10:47 AM
To: ccielab@groupstudy.com
Subject: NAT Outside
There is this example at Cisco Lab Press book:
int fa 0/0
ip ad 172.16.0.1
ip nat outside
!
ip nat outside source static udp 172.16.0.2 520 224.0.0.9 520
!
end
The goal is to unicast RIP packets instead of broadcast it to the
multicast address 224.0.09. I implemented it and it works really nice.
What I would appreciate is any tip about the interpretation of a "nat
outside" statement when reading it.
At the first glance I would say that this example would translate source
address whit IP 172.16.0.2 to 224.0.0.9 when the packet goes from
outside to inside; ok, it would really does it if there was a response
for RIP updates, which is not the case.
Is there a logical way to think about it? or just memorize?
This archive was generated by hypermail 2.1.4 : Fri Sep 03 2004 - 07:02:41 GMT-3