topic Re: Ip nat issue using multiple web servers in Network Security

Ip nat issue using multiple web servers

jonl711 — Mon, 11 Mar 2019 20:04:47 GMT

I currently have a webserver that is used for another business and I just install another webserver for another company.

on my router I have a IP NAT statement that reads as such:

ip nat inside source static tcp 192.168.2.248 80 203.153.225.77 80 extendable

this allows the 1st webserver access to and from the Internet.

When I try to add another line with a different IP Address such as

ip nat inside source static tcp 192.168.2.249 80 203.153.225.77 80 extendable

The router gives me an error stating the following:

% similar static entry (192.168.2.248 -> 203.153.225.77) already exists

I understand that this can be confusing in that packets destined for port 80 will go to the server .248, but is there a way to allow packet for port 80 to go to another server also? What is a better solution when using 2 webservers?

Thanks

Jon

Re: Ip nat issue using multiple web servers

csaxena — Fri, 11 Mar 2011 03:26:26 GMT

Hello Jon,

In case you wish to host multiple servers from inside, either you can use different ports redirecting to the servers on port 80. But, i am sure that will not solve your purpose. Another option is to use a different free public IP which is not port forwarding on port 80.

Server 1 (x.x.x.10 Port 80) ----> Public IP x.x.x.111 Port 80

Server 2 (x.x.x.11 Port 80) ----> Public IP x.x.x.112 Port 80

Hope this helps. Please reply back if you need any further assistance.

Regards,
Chirag
P.S.: Please mark this thread as answered if you feel your query is answered. Do rate helpful posts.

Re: Ip nat issue using multiple web servers

jonl711 — Fri, 11 Mar 2011 15:39:06 GMT

So if I understand you correctly I will need another public IP address from my isp, is this correct?

Jon

Re: Ip nat issue using multiple web servers

csaxena — Fri, 11 Mar 2011 16:54:17 GMT

Hi Jon,

Yes, to use port 80 for redirection you will require a new public IP.

Hope this helps. Please reply back if you need any further assistance.

Regards,
Chirag
P.S.: Please mark this thread as answered if you feel your query is answered. Do rate helpful posts.

Re: Ip nat issue using multiple web servers

jonl711 — Fri, 11 Mar 2011 17:34:44 GMT

I kinda thought that might be the case... ok thanks for confirming that... I'll give it a go and report back.

Re: Ip nat issue using multiple web servers

csaxena — Sat, 12 Mar 2011 03:17:45 GMT

Gr8. Mark this post answered for other to refer in future.

Ip nat issue using multiple web servers

lili Vachon — Sat, 03 Aug 2013 02:17:40 GMT

Hello,

How are you? I am in big trouble I am unable to configure 1 web server which is inside my organization. Can you please send your router running configuration. I need to configure it is very urgent please. Thank you.

Also Have a look at the links. Let me know Is there anything that is wrong with my configuration. Thank you.

https://supportforums.cisco.com/thread/2231684

https://learningnetwork.cisco.com/message/320091#320091

However, I can access web server Inside the organization but not from outside. Thank you.

Ip nat issue using multiple web servers

lili Vachon — Sat, 03 Aug 2013 02:18:21 GMT

Hello Chirag,

Can you help with my post.

https://learningnetwork.cisco.com/message/320091#320091

https://supportforums.cisco.com/thread/2231684

Ip nat issue using multiple web servers

johnlloyd_13 — Sat, 03 Aug 2013 04:08:01 GMT

hi lili,

please try avoiding duplicate posts.

i've made a reply over the WAN section/forum.

https://supportforums.cisco.com/message/4006724#4006724