Turris OS version 3.5.3
Kernel version 4.4.39-80079e1c1e5f9ca7ad734044462a761a-4
root@turris:~# cat /etc/resolv.conf
search lan
nameserver 127.0.0.1
root@turris:~# cat /tmp/resolv.conf.auto
Interface wan
nameserver 61.9.211.33
nameserver 61.9.211.1
search telstra.com.au
The ISP’s servers resolve the name just fine.
My configuration is pretty stock standard.
################### this doesn’t resolve
root@turris:~# nslookup download.ib.lbprod.nab.com.au
nslookup: can’t resolve ‘(null)’: Name does not resolve
nslookup: can’t resolve ‘download.ib.lbprod.nab.com.au’: Try again
root@turris:~#
################### just about everything else does resolve
root@turris:~# nslookup www.google.com
nslookup: can’t resolve ‘(null)’: Name does not resolve
Name: www.google.com
Address 1: 172.217.25.36
Address 2: 2404:6800:4006:802::2004 syd15s02-in-x04.1e100.net
root@turris:~#