We can't do much in case the fd is failing to be registered.
There should be a timeout that is catching this and it might
be able to repair it self.
Fixes: Coverity CID#1302854
In case the query for "hostname" will fail c-ares will append the
domain name of /etc/resolv.conf and query again. We don't want that
so claim we provide a list of domain names and then don't provide
any.
I didn't intend to have pushed the c-ares code to master yet.
c-ares is an asynchronous DNS resolver and we need it to
resolve the GGSN address. This is integrating the library
into our infrastructure. We will create and maintain a list
of registered FDs (c-ares is currently only using one of
them) and (re-)schedule the timer after events occurred.