RTP300 -- second computer does not connect to the Internet

Posts: 63 · Full Forum Member Joined: Jan 18, 2006 Posts: 63

Hello:

I have two computers, both XP Home, both rather fast.

I have a cable modem, and a Linksys RTP300 router. No phone connected at this point.

One computer can access the Internet, one cannot (and that is the problem). Both computers can "see" each other through the local network.

Non-working computer does not connect to the Internet whether Norton firewall is on or off. I do not know if it is significant, but I do not have a MAC address cloning or filtering enabled.

Setup Basic of the router differs from the manual: The router has

DNS 1:
DNS 2:
DNS 3:

in this window. I have nothing in them.

I have Start IP Address set to 192.168.15.101 (as per page 22 in the manual -- but I wonder why the default is set to 192.168.15.100)?

Any advice you can give as to why the second computer does not connect to the Internet would be appreciated.

Sincerely

Hans Leander

Posts: 3198 · Posted: Wed Jan 18, 2006 5:37 pm Post subject:

the default is fine (.100) but it probably doesn't make a difference.
when you do ipconfig on the non working one, what do you get for an ip? on the working one?
also, when you go to 192.168.15.1 what do you have under Status, Local Network, DHCP clients table? are both computers there with ip addresses assigned?

or, to try a quick fix, I'd turn off everything (including modem) for a good 30 seconds, then turn on the modem, wait, router, wait, comp1, wait, comp2, wait. it should really work like that. if not, I would say it's a software issue somewhere, be it with xp, internet explorer, etc. to test, open up a command window in the non working one and try something like ping www.yahoo.com

Posts: 63 · Full Forum Member Joined: Jan 18, 2006 Posts: 63

Hello reebok:

Here is the ipconfig info:

"Working" computer:

Connection-specific DSN suffix: -
IP Address: 192.168.15.102
Subnet mask: 255.255.255.0
Default gateway: 192.168.15.1

"Non-working computer"

Connection-specific DSN suffix: clvdoh.adelphia.net
IP Address: 192.168.15.101
Subnet mask: 255.255.255.0
Default gateway: 192.168.15.1

"Status, Local Network, DHCP clients table? are both computers there with ip addresses assigned?"

Yes!

I turned everything off earlier today for 10 minutes. No cigar.

Does the above tell you anything (I hope)?

Hans L

Posts: 63 · Full Forum Member Joined: Jan 18, 2006 Posts: 63

Ping did not find www.yahoo.com.

Hans L

Posts: 23 · Posted: Wed Jan 18, 2006 6:46 pm Post subject:

This definitely sounds like a DNS issue since you're able to ping both PCs. Check the DNS configuration of the WORKING computer and configure the non-working computer EXACTLY the same way.

Posts: 63 · Full Forum Member Joined: Jan 18, 2006 Posts: 63

Johnson98 -- that was it! Under TCP/IP Properties, General, I had "Use the following DNS server address" checked and the old address typed in.

Well, I learned a heck of a lot this time, and I want to thank you all who helped and tought me.

Regards,

Hans L

Posts: 350 · Vonage Forum Evangelist Joined: Dec 04, 2005 Posts: 350

Disable DNS proxy on the RTP300. Its in the basic setup section, about half way down. Reboot everything.

Posts: 63 · Full Forum Member Joined: Jan 18, 2006 Posts: 63

Hello Trekologer:

Since both computer now works, I will not make any more changes. However, I would be interested in knowing what the DNS Proxy function is. What happes if it is enabled and disabled, repsectively?

Hans L

Posts: 75 · Vonage Forum Senior Joined: Sep 06, 2005 Posts: 75

hanspl wrote:

Since both computer now works, I will not make any more changes. However, I would be interested in knowing what the DNS Proxy function is. What happes if it is enabled and disabled, repsectively?

dns proxy is where your router acts as a pseudo local dns server -- instead of your local workstations getting the dns server ips that your router received upon its dhcp lease from the isp and assigning them to you in your dhcp lease from your router to your local workstations, your router ip itself is the dns server that your local workstations use. the local workstations have 192.168.15.1 set as their dns server, so they contact the router for all dns lookups. the router receives those requests and then contacts the real dns servers for the lookups and then returns the results to the local workstation. it's also probable (though i'm not absolutely certain) it does some caching of those results, which may or may not speed up the dns lookup, but those benefits would be negligible in most cases. i'm not sure how good the rtp300's dns proxy is... in theory the technique is sound, but the implementation could be flawed. has anyone used the feature with great success?

Posts: 2257 · Posted: Thu Jan 19, 2006 12:18 pm Post subject:

blutarsky wrote:

i'm not sure how good the rtp300's dns proxy is... in theory the technique is sound, but the implementation could be flawed. has anyone used the feature with great success?

The WRTP54G (the wireless twin of the RTP300) has a pretty much useless implementation of DNS Proxy. I think it works OK with a single computer/client in place, but as soon as you add a second one - all bets are OFF.

One of the first things I recommend to anyone having "internet connection problems" on that series router (when I see the thread) is to hard code in their DNS information (or any of the open public DNS servers in the range 4.2.2.1 to 4.2.2.6) into their router, turn off the DNS proxy on the router, and do a lease release/renew at each client (or simply reboot each client).

Maybe they'll fix it someday, but turning off the proxy frees up memory and processor that can be used for more important things, like voice. Wink