NAT Host Resolver incorrectly sends A records in response to AAAA requests

[Mike Williams]

When I enable the NAT DNS proxy, I get "Question section mismatch" errors when trying to resolve names in my (Debian lenny) guest, and name-resolution hangs for a bit.

root@vm01:~# time host mirror.linux.org.au
mirror.linux.org.au has address 150.203.164.37
;; Question section mismatch: got mirror.linux.org.au/A/IN
;; Question section mismatch: got mirror.linux.org.au/A/IN
;; connection timed out; no servers could be reached
;; Question section mismatch: got mirror.linux.org.au/A/IN
;; Question section mismatch: got mirror.linux.org.au/A/IN
;; connection timed out; no servers could be reached

real	0m20.101s
user	0m0.016s
sys	0m0.032s

The culprit appears to be VirtualBox's DNS proxy, which is sending A responses to a AAAA request.

tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
listening on eth0, link-type EN10MB (Ethernet), capture size 96 bytes
19:56:44.901957 IP 10.0.2.15.36074 > 10.0.2.3.domain: 30452+ A? mirror.linux.org.au. (37)
19:56:44.904438 IP 10.0.2.3.domain > 10.0.2.15.36074: 30452* 1/0/0 A 150.203.164.37 (53)
19:56:44.906421 IP 10.0.2.15.34345 > 10.0.2.3.domain: 5541+ AAAA? mirror.linux.org.au. (37)
19:56:44.908385 IP 10.0.2.3.domain > 10.0.2.15.34345: 5541* 1/0/0 A 150.203.164.37 (53)
19:56:49.907358 IP 10.0.2.15.34345 > 10.0.2.3.domain: 5541+ AAAA? mirror.linux.org.au. (37)
19:56:49.911223 IP 10.0.2.3.domain > 10.0.2.15.34345: 5541* 1/0/0 A 150.203.164.37 (53)
...

[vasily Levchenko]

Could you please attach the log file.

[Mike Williams]

VM log

[Mike Williams]

Okay, I've attached the log for a VM with the NAT DNS proxy enabled. Was that the log-file you were after?

Nothing appears in the log when I try to resolve names, so I don't know how useful it will be.

[vasily Levchenko]

I've asked to make sure that we're definitely talking about dns proxy. And indeed we're talking about using host resolver mechanism. Which is rather different thing. I'll test your scenario with right variables and will back to you.

[Mike Williams]

Thanks Hachiman. Apologies for the confusion.

[vasily Levchenko]

I've been able to reproduce the issue, thanks for reporting. I'll offer a build to you with fix soon.

[vasily Levchenko]

Could you please verify that 4.0.0 b1 fixes issue for you?

[Frank Mehnert]

Please reopen if still relevant with VBox 4.0.