Re: intermittent failures and queries sent over TCP

2020-08-18 Thread 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

Re: intermittent failures and queries sent over TCP

2020-08-18 Thread Mark Andrews
Named will try TCP when the server returns TC=1 (TrunCated) in the UDP response. 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 ; <<>> Di

intermittent failures and queries sent over TCP

2020-08-18 Thread David Newman via bind-users
bind 9.11.5.P4 on Debian 10 Greetings. I recently had to migrate a nameserver from FreeBSD to Debian. It works fine most of the time but I've noticed a few intermittent resolution failures. After "gmail.com" failed to resolve I took a packet capture using tcpdump to listen to the result of the co