Thanks Quori, i can see it specifies 443, but how is SMTP (25) getting forwarded ??
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Browse All TopicsI'm a bit noob when it comes to CISCO configs. This one was written by our ISP, and then tinkered with from our PABX people.
We run our own exchange email server internally on 10.10.1.2, but I am moving this to 10.10.1.3. I can't see anywhere in the script to change this. Only reference to 10.10.1.2 i can find is to port forward (443) to existing mail server.
I want to have (443) and (25) port forwarding to 10.10.1.3.... I'm just not sure how it's being forwarded at the moment to 10.10.1.2... ??
The config is supposed to allow
- anything outgoing from 10.10.1.32 --> 10.10.1.40.
- incoming usual stuff to any (DNS, WWW, SSL, FTP)
- outgoing SMTP from 10.10.1.2 and 10.10.1.3 only
- VPN connections from 10.10.1.41 - 10.10.1.50
I have a hunch it's something to do with this???
route-map nonat permit 10
match ip address 102
If anyone can shed some light on this for me, it would be greatly appreciated.
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This is why I'm stumped.
It's definitely the "running-config" on our router.
It connects directly to the internet, and I've tested telnetting to port 25 from a remote location. It's definitely working, we are sending/receiving emails through SMTP with this router, directly to/from other email servers.
I'm using an application called "RouterTweak" to read/adjust the config, and i noticed that when trying to add a command "ip nat inside source static tcp 10.10.1.2 25 150.101.199.99 25 extendable"
I get error "% similar static entry (10.10.1.2 -> 150.101.179.92) already exists"
Also, to confirm "RouterTweak" wasn't giving me incorrect information, I checked the config using PuTTY.
Any ideas?
Thanks Quori,
With these line:
>> access-list 102 permit ip host 10.10.1.2 any
>> access-list 102 permit ip host 10.10.1.3 any
How would they cause port mapping? I thought they were just allowing outgoing connections from 10.10.1.2 and 10.10.1.3, and a few other IP's in that 102 list. When i added the 10.10.1.3 (new exchange server) to that 102 list, it was able to send outgoing mail on SMTP.
I don't know why i was getting errors when trying to add:
>> ip nat inside source static tcp 10.10.1.2 25 150.101.179.92 25 extendable
Or how the port mapping was working when i didn't have that command.
I ended up making my config look like this, and uploading it to startup config, then "reload"ing the router...
(Only showing relevant parts)
!
no ip http server
no ip http secure-server
ip nat inside source route-map nonat interface Dialer1 overload
ip nat inside source static tcp 10.10.1.1 21 150.101.179.92 21 extendable
ip nat inside source static tcp 10.10.1.2 25 150.101.179.92 25 extendable
ip nat inside source static tcp 10.10.1.2 443 150.101.179.92 443 extendable
!
access-list 102 permit ip host 10.10.1.2 any
access-list 102 permit ip host 10.10.1.3 any
Seems to work as predicted now, with all external mail/ssl going to 10.10.1.2, and outgoing permitted from 10.10.1.2 AND 10.10.1.3.. I also tested port forwading the SMTP/SSL to 10.10.1.3 which worked.
Do you think loading the script into startup config and "reload"ing the router made this work?
I'm still unsure why this works.
How were these lines causing port mapping?
>> access-list 102 permit tcp host 10.10.1.2 any eq smtp
>> access-list 102 permit tcp host 10.10.1.3 any eq smtp
And how was it working without the line
>> ip nat inside source static tcp 10.10.1.2 25 150.101.199.99 25 extendable
Thanks ?
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Answer for Membership
by: QuoriPosted on 2009-09-09 at 23:25:30ID: 25297753
ip nat inside source static tcp 10.10.1.2 443 150.101.199.99 443 extendable
This line is doing the current forwarding for that port.