Error while connecting to Active directory domain controller "An active directory domain controller could not be contacted"

Question

I have two EC2 servers on the private.network (they have the same Private su.net) on AWS and the first server is both AD DC and a DNS. DNS server info:

I have set the IP address of server 1 as DNS in server 2.

Now when I ping the IP address of the DNS server from server 2 it's successful.

I can ping the Computer name (dns.xyxyx.local) too;

Pinging just the domain name works as well:

But can't ping the just host name (dns);

And while trying to join the domain controller I get the following error:

Can anyone tell me why it can't join the AD DC? What am I doing wrong here?

Answer 1

It seems that AWS Security Group was blocking this. For now (Just test) I allowed all traffic and it's fixed.