Description
When using the host resolver DNS proxy (UseHostResolver?) from within a guest OS it is not possible to resolve host or domain names containing a dash ("-"). These both result in an NXDOMAIN return status for the DNS request instead.
This happens both for host names contained in the host system's /etc/hosts file as well as for hosts/domains that are passed on to the outside DNS.
Hosts and domains not containing a dash are being resolved OK both from /etc/hosts and outside DNS servers.
Demo case
/etc/hosts on host system:
192.168.200.11 skylight
192.168.200.21 s10-1
Guest configuration:
$ VBoxManage getextradata usrv01 enumerate
[...]
Key: VBoxInternal/Devices/e1000/0/LUN#0/Config/UseHostResolver, Value: 1
Guest's /etc/resolv.conf:
nameserver 10.0.2.3
DNS lookups for systems in host's /etc/hosts file:
$ dig skylight
; <<>> DiG 9.5.0-P2 <<>> skylight
;; global options: printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 8202
;; flags: qr aa rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 0
;; QUESTION SECTION:
;skylight. IN A
;; ANSWER SECTION:
skylight. 3600 IN A 192.168.200.11
;; Query time: 7 msec
;; SERVER: 10.0.2.3#53(10.0.2.3)
;; WHEN: Tue Dec 8 18:38:55 2009
;; MSG SIZE rcvd: 42
$ dig s10-1
; <<>> DiG 9.5.0-P2 <<>> s10-1
;; global options: printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NXDOMAIN, id: 47086
;; flags: qr aa rd; QUERY: 1, ANSWER: 0, AUTHORITY: 0, ADDITIONAL: 0
;; WARNING: recursion requested but not available
;; QUESTION SECTION:
;s10-1. IN A
;; Query time: 135 msec
;; SERVER: 10.0.2.3#53(10.0.2.3)
;; WHEN: Tue Dec 8 18:39:16 2009
;; MSG SIZE rcvd: 23
"Outside" DNS lookups:
$ dig www.sun.com
; <<>> DiG 9.5.0-P2 <<>> www.sun.com
;; global options: printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 19765
;; flags: qr aa rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 0
;; QUESTION SECTION:
;www.sun.com. IN A
;; ANSWER SECTION:
www.sun.com. 3600 IN A 72.5.124.61
;; Query time: 139 msec
;; SERVER: 10.0.2.3#53(10.0.2.3)
;; WHEN: Tue Dec 8 18:43:06 2009
;; MSG SIZE rcvd: 45
- With dash => NOK; name actually should resolve and does so on the host system
$ dig www.lrz-muenchen.de
; <<>> DiG 9.5.0-P2 <<>> www.lrz-muenchen.de
;; global options: printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NXDOMAIN, id: 56889
;; flags: qr aa rd; QUERY: 1, ANSWER: 0, AUTHORITY: 0, ADDITIONAL: 0
;; WARNING: recursion requested but not available
;; QUESTION SECTION:
;www.lrz-muenchen.de. IN A
;; Query time: 4 msec
;; SERVER: 10.0.2.3#53(10.0.2.3)
;; WHEN: Tue Dec 8 18:46:02 2009
;; MSG SIZE rcvd: 37
