Website not resolving via Umbrella but resolves with all others

[Ricky Sandhu]

Hi all,  we have a unique one.  There is an army engineering website https://nab.usace.army.mil that some of our users need to access however since we use Umbrella,  they are not able to get to it.  When performing NSLOOKUP against Umbrella,  the above domain does not return anything.  However if we switch to other DNS providers such as Google or Quad9,  the website resolves without any issues.  I checked under the Umbrella > Investigate and sure enough, this domain doesn't have an IPv4 address assignment.  

Please advise

[amojarra]

Hi @Ricky Sandhu 

I checked from my side and some Online DNS lookup site : 

mxtoolbox.com   ==> DNS No Valid NameServers Responded

dnschecker.org  ==> IPv4 and v6 : Sorry no record found  +  no name server

ping.eu               ==> connection timed out; no servers could be reached

NSLOOKUP: 

nab.usace.army.mil
Server: dns9.quad9.net
Address: 9.9.9.9

DNS request timed out.
timeout was 2 seconds.

======================

for army.mil I can find the Name server :

> set q=ns
> nab.usace.army.mil
Server: dns9.quad9.net
Address: 9.9.9.9

DNS request timed out.
timeout was 2 seconds.
*** Request to dns9.quad9.net timed-out
> army.mil
Server: dns9.quad9.net
Address: 9.9.9.9

Non-authoritative answer:
army.mil nameserver = ns02.army.mil
army.mil nameserver = ns01.army.mil

BUT no A record no AAAA record.

maybe it is better to check from your side as well to see if the issue is related to umbrella or the Records 

+++++++++++++++++++++++++++++++++++++++++++++++++++

++++   If you find this answer helpful, please rate it as such  ++++

+++++++++++++++++++++++++++++++++++++++++++++++++++