no record found for name but curl is perfectly happy

[svenstaro]

I'm trying to load test an internal host that is only resolvable via a special internal DNS and only IPv4. However, I can resolve that name just fine via nslookup, host, curl, and even hey but oha tells me

[69] no record found for name: internal.host type: A class: IN

I'm calling

oha --ipv4 -q 200 -n 2000 https://internal.host/test

However:

$ nslookup internal.host
Server:		127.0.0.1
Address:	127.0.0.1#53

internal.host	canonical name = redacted.
Name:	redacted
Address: 10.1.241.80

[hatoo]

[69] no record found for name: internal.host type: A class: IN

oha --ipv4 -q 200 -n 2000 https://internal.host/test

It looks only 69 lookups ware failed while there were 2000 requests.
Is it right? or all requests ware failed? Could you paste oha's all final output here?

[svenstaro]

All requests failed, I was just impatient.

Summary:
  Success rate:	0.0000
  Total:	10.0520 secs
  Slowest:	-inf secs
  Fastest:	inf secs
  Average:	0.0000 secs
  Requests/sec:	198.9657

  Total data:	0.00 B
  Size/request:	NaN
  Size/sec:	0.00 B

Response time histogram:

Latency distribution:
  10% in NaN secs
  25% in NaN secs
  50% in NaN secs
  75% in NaN secs
  90% in NaN secs
  95% in NaN secs
  99% in NaN secs

Details (average, fastest, slowest):
  DNS+dialup:	0.0000 secs, inf secs, -inf secs
  DNS-lookup:	0.0000 secs, inf secs, -inf secs

Status code distribution:

Error distribution:
  [2000] no record found for name: internal.host type: A class: IN

[hatoo]

Currently oha resolves a host using trust-dns-resolver.
So I think the issue is likely caused by trust-dns-resolver.

I created a small program that resolves a host via trust-dns-resolver and I believe it's almost the same as oha does.
https://github.com/hatoo/oha-56
Could you run this in your environment?
If this program also fails, we can confirm that this is an issue of trust-dns-resolver.

[svenstaro]

Yep, that suspicion is correct!
Output:

Error: no record found for name: internal.host type: A class: IN

[hatoo]

So, Please send this issue to https://github.com/bluejekyll/trust-dns

[svenstaro]

Ok done.

[svenstaro]

Alright so I've followed up with the author of trust_dns (read here) and as it turns out, I believe you've used it slightly incorrectly. You didn't grab the system config and as such, it defaulted to the Google DNS only while ignoring the resolv.conf.

I made #59 to fix this. It also has a second fix for spurious resolver errors and works around that by limiting the number of concurrent requests to 1. See https://github.com/bluejekyll/trust-dns/issues/933 for that.