[mythtv-users] Frequent mythfilldatabase download errors

[Gary Buhrmaster]

On Mon, Dec 1, 2014 at 2:54 PM, Dan Wilga
<mythtv-users2 at dwilga-linux1.amherst.edu> wrote:
.....
> Weird. I did manage to capture a log when it failed, and the problem was
> indeed "Host dd.schedulesdirect.org not found". This is the first time I've
> run into this, but I'm beginning to think you're right, Geoff. I'll try your
> suggestion of using a wrapper.

I would suspect the SchedulesDirect DNS infrastructure may not be
sufficient robust given the low TTLs, and especially if you are using
your own resolver rather than a "public" one that heavily caches and
improves the TTL regularly (not all ISP provided DNS servers are
created equal).

Last I checked, one of the schedulesdirect.org name servers were being
hosted by a corporate entity (probably owned/operated by someone
on the SchedulesDirect board).  The other was hosted in rackspace land
on what (by the name) appeared to be a shared service.  Due to the
realities of ISP peering, sometimes you are going to have problems
getting to either (or both) of those depending on which ISP you are
using.

I have no idea why SchedulesDirect is not using AWS Route 53
for their DNS infrastructure (since the back end services are running
on AWS).  Probably legacy reasons.

Personally, I never have observed problems with DNS resolution, but I
have a rather robust set of DNS resolvers and servers in my residence
and out in the cloud hosting my domains.

It likely will not hurt to attempt to resolve the name early to
"prime the pump" in your resolvers (or your ISPs resolvers) to
avoid the timeout.  It would be better to do the DNS debugging to
determine where the timeouts are occurring, and getting them fixed,
but random/rare failures are hard to debug.