intermittent failures and queries sent over TCP

[David Newman]

On 8/18/20 5:55 PM, Mark Andrews wrote:

> If you are getting RST responses check your firewall settings.  RST is often forged
> when TCP is blocked.  The root servers normally accept TCP connections.
> 
> % dig +tcp gmail.com @a.root-servers.net +dnssec

Bingo. This query failed before adding a rule to the upstream firewall
to allow outbound queries, and works now.

Thanks!

dn