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New Member

Problem with 1751 router


I have a 1751 router with numerous port forwarding statements configured to point to some internal web servers on my network. Everything works just fine but now and then one of the IP addresses 'freezes'.

All the other web sites are available and we can surf the web and get email so the router itself seems to be fine, we just lose access to a certain website. Rebooting the the server doesn't fix the problem so I don't think it's a server config issue. The only way to fix the problem is to reload the router.

The site is accessible for a random period of time then it locks up again. While the site is 'locked up' you can log in to the router but you get no reply when you ping either the public or the private IP address.

I have probably 25 forwarding statements config'd the same way and this is the only one that seems to have problems. Also, there are other sites on the same server that work fine. Here is the statement that I'm using:

ip nat inside source static tcp 192.168.1.x 80 x.x.x.x 80

I hope that this makes some sense, if you need more info please email me and I'll do my best to answer any questions you have. Thank you for any help provided.


VIP Purple

Re: Problem with 1751 router

Hi Brett,

does this also happen when that particular site is approached by IP address rather than DNS name (www.x.x)? I am thinking you could try to increase the DNS timeout (ip nat translation dns-timeout).



New Member

Re: Problem with 1751 router

Hi Georg,

Thanks for replying!

Yes, it happens even when trying the IP address. If you're on the local network, you can bring up the site by using the private IP in your browser (this rules out a server config problem), but if you try the actual public IP it doesn't work, you can't even ping it. Also, just FYI, when you're outside the network you still can't ping the public address or FQDN. I don't understand what could be causing the router to 'pick on' this particular address, there are many others on the same network ID (i.e. aaa.bbb.ccc.xx1, aaa.bbb.ccc.xx2, etc.) assigned to the same server and they all work fine.

Thanks again for your help and any suggestions.


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