Unbound randomly fails to resolve names

[lst_hoe02 at kwsoft.de]

Zitat von RayG via Unbound-users <unbound-users at lists.nlnetlabs.nl>:

> I did as requested and sent things in plain text but I have still had no
> response from anyone?
>
> This issue is causing me issues every day and I would just like to get it
> resolved one way or another.
>
> Any help or suggestions as to why Unbound is failing randomly would be of
> help.
>
> I should add that not every failure is caught by the event log. At least
> this shows that the failures are for a wide range of addresses:

Me too. Maybe...

As of now (23:34) two unbound instances fail to resolve cloudflare.net  
NS and anything using it as DNS service.

A "dig @127.0.0.1 cloudflare.net NS" lead to no servers could be  
reached, "dig @h.gtld-servers.net cloudflare.net NS" is working as  
expected. Nothing in the unboud log, and some minutes later all is  
working as expected again? In one case it is Ubuntu 16.04 with unbound  
1.5.8, the other one unbound 1.6.7 both validating DNSSEC.

Regards

Andi