[Building Sakai] Protocol family unavailable error

[Matthew Buckett]

On Thu, Sep 6, 2012 at 10:08 AM, David Horwitz <david.horwitz at uct.ac.za> wrote:
>
>> 2012-09-06 10:58:48,064 ERROR TP-Processor28
>> org.sakaiproject.calendar.impl.BaseExternalCalendarSubscriptionService
>> - Unable to read calendar subscription
>> '/calendar/ical/*************%40group.calendar.google.com/public/basic.ics'
>> from URL (I/O Error):
>> https://www.google.com/calendar/ical/rv9klcp1bn06etdd4aarcm735c%40group.calendar.google.com/public/basic.ics
>> java.net.SocketException: Protocol family unavailable
>
>
> All seem to be from Google. Now googling and looking at our config I
> suspect that this is IPv6 related - the DNS lookup is returning  an IPv6
> address but our Vula nodes don't have IPv8 support.

IPv8 wow!

Have you tried telling the JVM to prefer IPv4 stack (system property):

java.net.preferIPv4Stack=true

although it should be using the IPv4 addresses in preference to IPv6
ones even when using the IPv6 stack, the other one to try is:

java.net.preferIPv6Addresses=false

-- 
  Matthew Buckett, VLE Developer, IT Services, University of Oxford