There are a couple of issues here. First, the "ip nat inside source static tcp 192.168.129.19 25 63.x.x.34 25 extendable" command will simply disappear from the running config anywhere from immediately to a few hours after being entered. Any ideas as to why this would be happening?
Second, I'm seeing some strange entries in the translation table such as:
63.x.x.40 is the ip address of the Fa0/0 interface. So, it seems to me that the router is double-translating traffic, i.e. 192.168.129.34 gets translated to 63.x.x.34 which then gets translated to 63.x.x.40. Is this possible? I thought once a packet had been permitted or denied through the NAT process, it was then forwarded out the interface.
The goal here is to send port 80 and 443 to a Web mail server but send port 25 to the SMTP server. Outbound traffic from the hosts in the SMTP-NAT-out ACL needs to show up on the Internet as 63.x.x.34.
I've been looking at NAT features such as extendable, NAT virtual interfaces, and route maps but I have yet to find an article on CCO or NPC that really explains when and why these features would be used and what problems they solve.
If anybody has any ideas as to why we're seeing the disappearing command or any suggestions as to other possible approaches to the goals, they would be much appreciated!
We are pleased to announce availability of Beta software for 16.6.3. 16.6.3 will be the second rebuild on the 16.6 release train targeted towards Catalyst 9500/9400/9300/3850/3650 switching platforms. We are looking for early feedback from custome...