named won't shut down after a timed out attempt to forward dynamic update
When named
attempts to forward a dynamic DNS update to a non-responsive primary, it won't properly shutdown on SIGTERM
once the TCP connection times out.
Steps to reproduce
- start named with this config
options {
port 5353;
listen-on { 10.53.0.3; };
};
zone "noprimary" {
type secondary;
allow-update-forwarding { any; };
primaries port 5555 { 10.53.0.4; };
};
-
simulate a non-responsive primary - the key is to accept the TCP connection but simply don't respond to anything:
netcat -l -p 5555
-
send the following nsupdate
local 10.53.0.1
server 10.53.0.3 5353
zone noprimary
update add unsigned.noprimary. 600 A 10.10.10.1
send
-
wait 30 seconds for the following log line to appear in named:
zone noprimary/IN: could not forward dynamic update to 10.53.0.4#5555: timed out
-
send
SIGTERM
to named