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help configuring 851 router

I have an 851 router which has a very basic configuration on it. Everything seems to be configured correctly, however I am having trouble accessing my web server. I can only get to it some of the time. The rest of the time it times out.

It seems like something is bouncing. When I can get to it, I can access everything easily for about 30 seconds. Then I can't get to it for a couple of minutes and then I can get to it again for another 30 seconds (or so) and so on.

I don't have access to the config at the moment.

- the web server can get out to the internet consistantly

- the DNS does resolve to the correct address for my web server

- everything seems to go out fine. The trouble seems to be incoming traffic only.

- through the SDM gui configuation manager, I chose the "high" option for the firewall security.

- I am using NAT to access the server.

If anyone can help, I'd greatly appreciate it.



Re: help configuring 851 router


Check the speed/duplex setting of both the server and the port in the router where it is connected. If possible, hardcode them to 100Mbps/Full-duplex. The cabling used should be straight



Community Member

Re: help configuring 851 router

Thanks for the quick reply. The server is set to Auto and it shows 100mb full duplex. How do I check the port of the router?

Hall of Fame Super Gold

Re: help configuring 851 router

Hi, are you using PPPoE ? if so you need a setting like "ip tcp adjust-mss 1452" under dialer1.

Hope this helps, please rate post if it does!

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