`Error: queryCname ENODATA blog.nodejs.org` running `test/internet/test-dns.js`

[richardlau]

Starting from 13 July daily build test/internet/test-dns.js has been failing in node-test-commit-custom-suites-freestyle (test-internet) and on GH actions.

e.g. https://ci.nodejs.org/job/node-test-commit-custom-suites-freestyle/31576/console

08:20:22 not ok 9 internet/test-dns
08:20:22 ---
08:20:22 duration_ms: 137.08100
08:20:22 severity: fail
08:20:22 exitcode: 1
08:20:22 stack: |-
08:20:22 test_reverse_bogus
08:20:22 test_resolve4_ttl
08:20:22 looking up nodejs.org..
08:20:22 test_resolve6_ttl
08:20:22 nodejs.org = 104.20.22.46,104.20.23.46
08:20:22 test_resolveMx
08:20:22 test_resolveMx_failure
08:20:22 test_resolveNs
08:20:22 test_resolveNs_failure
08:20:22 test_resolveSrv
08:20:22 test_resolveSrv_failure
08:20:22 test_resolvePtr
08:20:22 test_resolvePtr_failure
08:20:22 test_resolveNaptr
08:20:22 test_resolveNaptr_failure
08:20:22 test_resolveSoa
08:20:22 test_resolveSoa_failure
08:20:22 test_resolveCaa
08:20:22 test_resolveCaa_failure
08:20:22 test_resolveCname
08:20:22 16 tests completed
08:20:22 (node:14833) internal/test/binding: These APIs are for internal testing only. Do not use them.
08:20:22 (Use `node --trace-warnings ...` to show where the warning was created)
08:20:22 node:internal/errors:496
08:20:22 ErrorCaptureStackTrace(err);
08:20:22 ^
08:20:22 
08:20:22 Error: queryCname ENODATA blog.nodejs.org
08:20:22 at QueryReqWrap.onresolve [as oncomplete] (node:internal/dns/promises:251:17) {
08:20:22 errno: undefined,
08:20:22 code: 'ENODATA',
08:20:22 syscall: 'queryCname',
08:20:22 hostname: 'blog.nodejs.org'
08:20:22 }
08:20:22 
08:20:22 Node.js v21.0.0-pre
08:20:22 ...

This was the next day after we added a CNAME entry for blog.nodejs.org: nodejs/build#3404 (comment)
Previously blog.nodejs.org was caught by the (now removed) CNAME entry for *.nodejs.org.

[richardlau]

I ran a few dns.resolveCname() calls for the other CNAME entries we have and it looks like any of the proxied ones are also returning ENODATA but the non-proxied ones succeed. The previous *.nodejs.org CNAME entry was not proxied: nodejs/build#3404 (comment)

I've removed the proxy setting for blog.nodejs.org -- this didn't immediately fix the issue but trying on a different system worked and I've just tried again on the original system I was testing on and it now works so there's probably some DNS TTL caching going on.

CI: https://ci.nodejs.org/job/node-test-commit-custom-suites-freestyle/31687/

[richardlau]

CI: https://ci.nodejs.org/job/node-test-commit-custom-suites-freestyle/31687/

test-dns.js passed 🎉. I'll open another issue for the test-net-autoselectfamily-timeout-close failure.