Red Hat Bugzilla – Bug 143744
dig and nsupdate have no option to force connection via IPv4 or IPv6 and also no fallback
Last modified: 2007-11-30 17:10:57 EST
Description of problem:
In case of an existing IPv6 connectivity, nsupdate and dig are
preferring the use of IPv6 sockets.
If now on client or server side the IPv6 connectivity is broken, no
force or fallback is possible.
dig got in 9.3.0 two options (-4 and -6) to force the connectivity.
nsupdate didn't get one in 9.3.0
Version-Release number of selected component (if applicable):
Steps to Reproduce:
1. Setup IPv6 connectivity, but break e.g. the tunnel.
2. run dig or nsupdate
Actual Results: # dig www.bieringer.de @ns.bieringer.de
; <<>> DiG 9.2.4 <<>> www.bieringer.de @ns.bieringer.de
;; global options: printcmd
;; connection timed out; no servers could be reached
cat /tmp/nsupdate.txt | nsupdate
; Communication with server failed: timed out
Expected Results: For dig and nsupdate: fallback to other protocol,
if given DNS server name has A and AAAA record and no preselection was
done (in case of dig, because nsupdate didn't understand any
preselection at all).
For nsupdate, I currently created a workaround with a wrapper to set
local <ipv4address> and server <ipv4address> explicitly, which results
in IPv4 socket use.
Using bind-9.2.4-4 for FC3 will solve the timeout issue - you can
download it from:
and I've also fixed it in bind-9.3.0 for FC3, available from:
Please try one of these new versions - they should fix the problem -
I cannot duplicate it with them.
For bug #140528 , I put a patch into the 'libdns' resolver library
to immediately try the next available server address on NETUNREACH
/ HOSTUNREACH errors, that ISC have accepted for inclusion in the
next release of BIND ( ISC bug 13153 ), so the 'dig' or 'nsupdate'
utilities, which also use libdns, will no longer time out. With
dig you can also use the +time and +tries options to increase the
I'm in the process of getting one of these new versions pushed into