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This problem concerns an internal DNS server that for some reason sometimes fails to resolve the host names of some machines on the network. When it fails to resolve a host name, and this can happen on any client machine, the following commands return the following:

ipconfig /displaydns:
vm1host.domain.local - Name does not exist.

nslookup vm1host:
dnsserver1.domain.local can't find vm1host: Non-existent domain

ping vm1host:
Ping request could not find host vm1host. Please check the name and try again.

tracert vm1host:
Unable to resolve target system name vm1host.

nslookup vm1host.domain.local :
dnsserver1.domain.local can't find vm1host.domain.local: Non-existent domain

ping vm1host.domain.local:
Ping request could not find host vm1host.domain.local Please check the name and try again.

tracert vm1host.domain.local:
Unable to resolve target system name vm1host.domain.local.

nslookup <vm1-ip-address>:
Works Ok...

ping <vm1-ip-address>:
Works Ok...

tracert <vm1-ip-address>: Works Ok... (also displays vm1host.domain.local)

Interestingly, tracert resolves the name appropriately using only 2 hops.

Even if subsequently nslookup/ping the host name, I get the same error messages above.

Flushing the dns does nothing, and even if it did it would not solve the underlying problem since it is experienced by all client machines.

What does the failure of nslookup/ping but the success of tracert suggest about the underlying problem?

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  • 1
    Which OS is installed on those computers?
    – VL-80
    Jan 18, 2014 at 20:46
  • Is it constant problem with particular names (you never can resolve them)? Or they become problematic periodically?
    – VL-80
    Jan 18, 2014 at 20:58
  • And do your domain names really end in local.?
    – JdeBP
    Jan 20, 2014 at 20:52

1 Answer 1

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Your tracert to the IP address is utilizing a reverse DNS lookup, that is to say it is querying the DNS server for the name to match the IP you entered. (As opposed to a regular forward DNS lookup where your computer queries the DNS server for an IP based on the name you entered.)

If, as in your case, you're not getting responses for a forward DNS lookup, but ARE getting responses from a reverse DNS lookup, then the issue would most likely be that no A Record exists for that host on the DNS server.

However, since you are getting the correct name for the host when your computer performs a reverse DNS lookup, it is likely that a PTR Record for the IP address does exists on the DNS server.

For more information on this, I recommend checking out the Wikipedia page on DNS record types.

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