[CentOS] inconsistent DNS results - ping vs dig vs nslookup

[Les Mikesell]

On 6/22/2011 3:30 PM, Robert Henrichs wrote:
>
>
>     what's a good link to read about how the resolv.conf file is
> constructed?  esp. the "search" entry?

The 'search' should only apply if you don't supply the domain portion of 
the name.  Each nameserver address should be queried until one responds.

> ***
> My nsswitch.conf file does contain:
>    hosts:      files dns
> (this is an interesting file I'll have to revisit...thanks).

The part that doesn't make sense yet is that your dns is working as 
shown by the dig/nslookup queries, but ping/wget are failing to look up 
the name.  You might get random success/failure if some of the 
nameservers in resolv.conf are misconfigured.  Seems like a long shot 
but try:
dig @server_address www.henrichs.org
for each of the namesever addresses, then maybe
strace ping www.henrichs.org
and wade through the output to see if it has trouble loading the 
resolver library or something.

-- 
   Les Mikesell
    lesmikesell at gmail.com