I have an issue with name resolution on my home network. Computer names are being resolved to public ip addresses instead of to their private ip address. My home network consists of a Motorola Surfboard Cable Modem, a Belkin Surf N300 wireless router with the latest firmware, two PCs with 64-bit Windows 7 Pro, one PC with WinXP SP3 and a D-Link DSM-520 Media Player. All the computers are connected to the router through cable. The DSM-520 is connected via wireless. DHCP is enabled on the Belkin router. The Local Domain Name setting in the Belkin's LAN Settings is "colt". The host files on the PCs contain only comments. My Win7 PC's name is alshotasus, my wife's Win7 PC's name is ellenshotpc. The WinXP system's name is gw-mediapc. According to the DHCP Client list in the Belkin router the router has assigned these ip addresses: alshotasus 192.168.2.3 ellenshotpc 192.168.2.10 gw-mediapc 192.168.2.2 But, when I ping gw-mediapc (or gw-mediapc.colt) from alshotasus, ping reports the ip address as 204.232.162.154. C:\Windows\system32>ping gw-mediapc.colt Pinging gw-mediapc.colt [204.232.162.154] with 32 bytes of data: Reply from 204.232.162.154: bytes=32 time=61ms TTL=112 Reply from 204.232.162.154: bytes=32 time=61ms TTL=112 Reply from 204.232.162.154: bytes=32 time=62ms TTL=112 Reply from 204.232.162.154: bytes=32 time=65ms TTL=112 Ping statistics for 204.232.162.154: Packets: Sent = 4, Received = 4, Lost = 0 (0% loss), Approximate round trip times in milli-seconds: Minimum = 61ms, Maximum = 65ms, Average = 62ms (Note that sometimes the ip address returned by ping is a different public address.) When I ping ellenshotpc (or ellenshotpc.colt) ping reports the ip address as 184.106.31.189 (Sometimes the ip address returned by ping is a different public address.) Curiously, when I ping my system, alshotasus (or alshotasus.colt), ping reports the ip address is the same as for ellenshotpc: 184.106.31.189 Here's the output from ipconfig when run on my PC: C:\Windows\system32>ipconfig /all Windows IP Configuration Host Name . . . . . . . . . . . . : AlsHotAsus Primary Dns Suffix . . . . . . . : Node Type . . . . . . . . . . . . : Hybrid IP Routing Enabled. . . . . . . . : No WINS Proxy Enabled. . . . . . . . : No DNS Suffix Search List. . . . . . : colt Ethernet adapter Local Area Connection: Connection-specific DNS Suffix . : colt Description . . . . . . . . . . . : Realtek PCIe GBE Family Controller Physical Address. . . . . . . . . : 00-26-18-E1-82-92 DHCP Enabled. . . . . . . . . . . : Yes Autoconfiguration Enabled . . . . : Yes IPv4 Address. . . . . . . . . . . : 192.168.2.3(Preferred) Subnet Mask . . . . . . . . . . . : 255.255.255.0 Lease Obtained. . . . . . . . . . : Saturday, January 01, 2011 7:26:45 AM Lease Expires . . . . . . . . . . : Tuesday, February 07, 2147 4:50:58 PM Default Gateway . . . . . . . . . : 192.168.2.1 DHCP Server . . . . . . . . . . . : 192.168.2.1 DNS Servers . . . . . . . . . . . : 192.168.2.1 NetBIOS over Tcpip. . . . . . . . : Enabled Tunnel adapter isatap.colt: Connection-specific DNS Suffix . : colt Description . . . . . . . . . . . : Microsoft ISATAP Adapter Physical Address. . . . . . . . . : 00-00-00-00-00-00-00-E0 DHCP Enabled. . . . . . . . . . . : No Autoconfiguration Enabled . . . . : Yes Link-local IPv6 Address . . . . . : fe80::5efe:192.168.2.3%12(Preferred) Default Gateway . . . . . . . . . : DNS Servers . . . . . . . . . . . : 192.168.2.1 NetBIOS over Tcpip. . . . . . . . : Disabled Tunnel adapter Teredo Tunneling Pseudo-Interface: Connection-specific DNS Suffix . : Description . . . . . . . . . . . : Teredo Tunneling Pseudo-Interface Physical Address. . . . . . . . . : 00-00-00-00-00-00-00-E0 DHCP Enabled. . . . . . . . . . . : No Autoconfiguration Enabled . . . . : Yes IPv6 Address. . . . . . . . . . . : 2001:0:4137:9e76:2c35:2473:e719:752f(Preferred) Link-local IPv6 Address . . . . . : fe80::2c35:2473:e719:752f%13(Preferred) Default Gateway . . . . . . . . . : :: NetBIOS over Tcpip. . . . . . . . : Disabled Here's the output of nbtstat -c Local Area Connection: Node IpAddress: [192.168.2.3] Scope Id: [] NetBIOS Remote Cache Name Table Name Type Host Address Life [sec] ------------------------------------------------------------ ELLENSHOTPC <20> UNIQUE 192.168.2.10 545 GW-MEDIAPC <20> UNIQUE 192.168.2.2 595 Note that the ip addresses reported by nbtstat are identical to the ip addresses in the Belkin router's DHCP client list. This name resolution issue started after I replaced an old Linksys BEFSR41 with the Belkin N300. I discovered the issue the first time I tried to connect with Remote Desktop by computer name. Now, I have to use the remote PC's ip address in order to connect with Remote Desktop. Disabling the Windows Firewall on the PC's does not help. TIA AlAl

Both of those addresses resolve to Rackspace, a cloud services provider that probably hosts the "colt" domain. Try removing the "colt" domain name from your router's config, unless you are the actual registered owner of that domain. For a home network with no actual server set up you really don't need a domain name anyway, so just leave it blank.

Thanks for your response. There was much detail I left out of my original post because it was already so long. I have tried a number of different domains besides colt and they all behave the same. For example, I just tried marg3498 (an attempt at a name that is somewhat random and unlikely to be used by anyone else). After changing the Local Domain Name in the router to margh3498 I did an ipconfig /release followed by an ipconfig /renew. The computer names on my network still resolve to external IPs. It seems unlikely that there are actually other computers on the internet with names like alshotasus.colt and alshotasus.marg3498. I've tired setting a blank Local Domain Name, but, unfortunately, the Belkin N300 LAN configuration page doesn't allow the Local Domain Name setting to be empty. I'm have to admit that I don't know much about DNS, name resolution on home networks, etc, so if I've made some incorrect assumptions, I'm very willing to be corrected. - Al Al

I just suspect that the firewall in the router blocks ICMP so you get a virtual or a fake address respond. It may protect your computers from hacks.Please remember to click Mark as Answer on the post that helps you, and to click Unmark as Answer if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread.

Hi Arthur, The router does block pinging the WAN port. I tested your theory by disabling the firewall in the router. Sadly, it did not change the behavior of name resolution. (I quickly enabled the firewall after the test.) While researching this problem I learned that name resolution is different for ping than for nslookup so I tried nslookup on the names of the PCs on my network. The results were interesting (at least to me) in that ping and nslookup resolved to different ips. Name private ip ip from ping ip from nslookup ellenshotpc 192.168.2.10 184.106.31.189 204.232.162.154 I remain puzzled. I'm not a network guy by any means, but I'm starting to think that I am going to have to install ethereal and run some traces while I test. Thanks, AlAl