Terraform PowerDNS provider have troubles in checking the current state of the DNS records. The error is provided below (along with trace debug (TF_LOG=DEBUG)).
powerdns_record.dns_a_worker_pub[2]: Refreshing state... (ID: k8s-worker-3.k8s-debs-2.cluster.local.:::A)
lking "powerdns_record.dns_a_worker_pub[1]"
2019/03/05 22:52:32 [TRACE] vertex 'root.powerdns_record.dns_a_worker_pub[1]': walking
2019/03/05 22:52:32 [TRACE] vertex 'root.powerdns_record.dns_a_worker_pub[1]': evaluating
2019/03/05 22:52:32 [TRACE] [walkRefresh] Entering eval tree: powerdns_record.dns_a_worker_pub[1]
2019/03/05 22:52:32 [TRACE] root: eval: *terraform.EvalSequence
2019/03/05 22:52:32 [TRACE] root: eval: *terraform.EvalGetProvider
2019/03/05 22:52:32 [TRACE] root: eval: *terraform.EvalReadState
2019/03/05 22:52:32 [TRACE] root: eval: *terraform.EvalRefresh
2019/03/05 22:52:32 [TRACE] dag/walk: walking "powerdns_record.dns_a_worker_pub[2]"
2019/03/05 22:52:32 [TRACE] vertex 'root.powerdns_record.dns_a_worker_pub[2]': walking
2019/03/05 22:52:32 [TRACE] vertex 'root.powerdns_record.dns_a_worker_pub[2]': evaluating
2019/03/05 22:52:32 [TRACE] [walkRefresh] Entering eval tree: powerdns_record.dns_a_worker_pub[2]
2019/03/05 22:52:32 [TRACE] root: eval: *terraform.EvalSequence
2019/03/05 22:52:32 [TRACE] root: eval: *terraform.EvalGetProvider
2019/03/05 22:52:32 [TRACE] root: eval: *terraform.EvalReadState
2019/03/05 22:52:32 [TRACE] root: eval: *terraform.EvalRefresh
2019/03/05 22:52:32 [ERROR] root: eval: *terraform.EvalRefresh, err: powerdns_record.dns_a_worker_priv.1: Error checking PowerDNS Record: invalid character 'C' looking for beginning of value
2019/03/05 22:52:32 [ERROR] root: eval: *terraform.EvalSequence, err: powerdns_record.dns_a_worker_priv.1: Error checking PowerDNS Record: invalid character 'C' looking for beginning of value
2019/03/05 22:52:32 [TRACE] [walkRefresh] Exiting eval tree: powerdns_record.dns_a_worker_priv[1]
It is something in terms of evaluating the entry. Cannot figure out what is actually wrong.
I have already figured it out by checking the traffic with tcpdump. It was connecting to the proxy i got specified under http_proxy and https_proxy enviromental variables.
Sorry for bothering you. Therefore the response was unexpected. I was surprised that the proxy is used even when connecting to port 8080.