Where and how I should look for upstream DNS servers.
ping
failing, this may not work. drill @127.0.0.1 de.pool.ntp.org
drill @192.168.1.1 de.pool.ntp.org
drill @8.8.8.8 de.pool.ntp.org
drill @127.0.0.1 de.pool.ntp.org
drill @192.168.1.1 de.pool.ntp.org
drill @8.8.8.8 de.pool.ntp.org
nameserver 127.0.0.1
nameserver 192.168.186.2