I am operating on a LAN closed off from the internet, and there are a few devices (A, B, C, ...) connected via ethernet cable to a single router making this LAN possible. Operating system on all devices: Windows 10.
- Why is LLMNR failing, when DNS doesn't?
- Why does 'ping A' use LLMNR, while 'ping A.' uses DNS?
- Is there any way to force nslookup to use LLMNR, instead of DNS, and why?
- What exactly is happening when I append a '.' to the hostname, for both 'ping' and 'nslookup'?
- How do you know the answers to these questions (field of work & type of experience)?
THE CONTEXT OF THIS QUESTION CAN BE FOUND BELOW
both yield the following satisfactory output
Server: localDnsServerName Address: 192.168.1.1 Name: A Address: 192.168.1.X
yields a satisfactory output ('.' is appended to the hostname being queried)
Pinging A [192.168.1.x] with 32 bytes of data: Reply from 192.168.1.X: byte=32 time<1ms TTL=128 Reply from 192.168.1.X: byte=32 time<1ms TTL=128 Reply from 192.168.1.X: byte=32 time<1ms TTL=128 Reply from 192.168.1.X: byte=32 time<1ms TTL=128 Ping statistics for 192.168.1.X: Packets: Sent = 4, Received = 4, Lost = 0 (0% loss), Approximate round trip times in milli-seconds: Minimum = 0ms, Maximum = 0ms, Average = 0ms
However, the following command
yields an unsatisfactory output
Ping request could not find host A. Please check the name and try again.
Upon further investigation, via Wireshark, I see the nslookup commands and 'ping A.' command result in successful standard queries using the DNS protocol.
However, 'ping A' results in a standard query using the LLMNR protocol, which fails.
Via the RFC 4795, Abstract for LLMNR:
"The goal of Link-Local Multicast Name Resolution (LLMNR) is to enable name resolution in scenarios in which conventional DNS name resolution is not possible. LLMNR supports all current and future DNS formats, types, and classes, while operating on a separate port from DNS, and wtih a distinct resolver cache. Since LLMNR only operates on the local link, it cannot be considered a substitute for DNS."
Additional tag: 'llmnr'
I would have added the mentioned additional tag officially, but I don't have a reputation of at least 300 to create a new tag. Please add this tag, if it is possible to tag a question after it is created, by editing this question.