Internernal view is answering to external ping

[John Wobus]

Many use ping to check DNS issues but doing so brings in
another factor: the client's os/resolver/caching.
The 'dig' utility aims to work around this.  If 'dig'
(to the DNS server's numeric address) and 'ping' DNS resolutions
differ, you have good evidence it is a client issue.
On the other hand if both give the same unwanted answer,
you have evidence it is a server configuration issue.

John Wobus
Cornell University IT