We use the Technicolor TG582n router in work which is a LAN of about 10 PCs with internet connection over DSL and filesharing in Workgroup rather than domain - we have no Windows servers that do DNS, Active Directory or WINS. Most of the computers are fixed static IP addresses with some using dynamic IP from the DHCP pool on the Technicolor router.
I noticed something while setting a new PC up. When using a dymamic IP address the computer could not access shared folders on the network. I checked using ping to that computer, pinging its NETBIOS name and it failed. It was trying to ping a competely different IP address. Ping would work if I specified the remote PC's correct IP address but if I specified NETBIOS name ping would attempt to ping an IP address that was not even existing on the network. Did a Wireshark packet trace and Technicolor router is answering a DNS query that is generated by the local PC (the one sending ping). From reading up on NETBIOS it is normal for trying DNS first and if a Windows server existed on network that would answer correctly matching NETBIOS to correct IP address. Without a DNS server or WINS server it should then default to broadcast and get an answer that way.
Does anyone know what on earth is happening here? Why is that router attempting to answer NETBIOS lookups (from DNS query). Would be fine if gave correct answer but it is just giving wrong answers. Replicated the issue on another PC, doing same thing answering DNS query for NETBIOS name but giving incorrect IP address in answer. By the way have tried it with DNS servers specified in local machine as Google public DNS servers or leaving blank to allow use of Plusnet DNS servers and has no effect so does not seem to be corrupt DNS servers but buggy router.
Have also verified issue by Telnetting into router directly and performing the DNS lookup:
{admin}=>:dns client nslookup host=C194.lan
Name: C194.lan
Address: 192.168.0.136
Aliases: none
{admin}=>:dns client nslookup host=C240.lan
Name: C240.lan
Address: 192.168.0.135
These are both incorrect answers it is giving!
DNS config info obtained from Telnet session:
{admin}=>dns server config
domain : lan
timeout : 15s
suppress : 0
state : enabled
trace : disabled
syslog : disabled
spoofing : enabled
spoof ip : 198.18.1.0
filter response : disabled
UPDATE: I have found a workaround by issuing "dns server flush" command. But why did this incorrect info get into router in first place. Why does it not keep correct NETBIOS info?
