[Libguestfs] [PATCH] appliance: Disable ipv6 in the appliance because qemu usernet is ipv4 only

[Richard W.M. Jones]

On Thu, Jan 23, 2014 at 11:44:52PM +0100, Olaf Hering wrote:
> Signed-off-by: Olaf Hering <olaf at aepfle.de>
> ---
> 
> Untested in this environment.
> 
>  appliance/init | 4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/appliance/init b/appliance/init
> index b25ea26..cc8c978 100755
> --- a/appliance/init
> +++ b/appliance/init
> @@ -71,6 +71,10 @@ for f in /sys/block/{h,s,ub,v}d*/queue/scheduler; do echo noop > $f; done
>  # Update the system clock.
>  hwclock -u -s
>  
> +# Disable ipv6 because host names resolve to ipv4 and ipv6
> +# Resolver may prefer ipv6 and qemu usernet does only ipv4
> +for f in /proc/sys/net/ipv6/conf/*/disable_ipv6; do if test -w $f ; then echo 1 > $f; fi; done

There's no error checking in init, so this should work:

  for f in /proc/sys/net/ipv6/conf/*/disable_ipv6; do echo 1 > $f; done

However I don't understand why disabling IPv6 should be necessary.  If
sites resolve to AAAA+A records, then presumably it's going to choose
the A (IPv4) route since no IPv6 route exists.  If a site resolves to
only an AAAA record, then it's not reachable whatever we do.

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
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