Windows 2k8 R2 DNS server – DNS request timed out

I have a problem with fresh installed AD/DNS server.

I have one domain controller that works as it should, without any issues.

Tried to install second DC at the second office. I've installed Active Directory role, executed dcpromo – everything went smoothly. But the DNS server on that new server doesn't work. When I tried to execute nslookup command, it says "DNS request timed out. timed out was 2 seconds."
And I don't have any ideas why.
I've checked:
– DNS server service is running;
– it received info about zones from AD;
– DNS server is listening on all ip addresses (netstat confirms it);
– DNS has a reverse lookup zone with the ptr record for the new server;
– I don't see any DNS-related errors in the Event Viewer;
– firewall is completely off for a tests.

ipconfig from the server. 192.168.250.125 – LAN address, 10.0.9.103 – VPN
tunnel, 192.168.0.11 – main DC

C:\Users\myuser>ipconfig /all

Windows IP Configuration

   Host Name . . . . . . . . . . . . : EX-DC2
   Primary Dns Suffix  . . . . . . . : MyDomain.com
   Node Type . . . . . . . . . . . . : Hybrid
   IP Routing Enabled. . . . . . . . : No
   WINS Proxy Enabled. . . . . . . . : No
   DNS Suffix Search List. . . . . . : MyDomain.com

Ethernet adapter Local Area Connection 2:

   Connection-specific DNS Suffix  . : mydomain.com
   Description . . . . . . . . . . . : Intel(R) PRO/1000 MT Network Connection #2
   Physical Address. . . . . . . . . : 00-0C-29-C6-AF-56
   DHCP Enabled. . . . . . . . . . . : No 
   Autoconfiguration Enabled . . . . : Yes
   IPv4 Address. . . . . . . . . . . : 192.168.250.125(Preferred)
   Subnet Mask . . . . . . . . . . . : 255.255.255.0 
   Default Gateway . . . . . . . . . : 192.168.250.1
   DNS Servers . . . . . . . . . . . : 192.168.250.125
                                       192.168.0.11
   NetBIOS over Tcpip. . . . . . . . : Enabled

Ethernet adapter OpenVPN:

   Connection-specific DNS Suffix  . : mydomain.com
   Description . . . . . . . . . . . : TAP-Windows Adapter V9
   Physical Address. . . . . . . . . : 00-FF-8A-C9-A1-FE
   DHCP Enabled. . . . . . . . . . . : Yes 
   Autoconfiguration Enabled . . . . : Yes
   IPv4 Address. . . . . . . . . . . : 10.0.9.103(Preferred)
   Subnet Mask . . . . . . . . . . . : 255.255.255.0
   Lease Obtained. . . . . . . . . . : Wednesday, January 24, 2018 3:17:18 AM
   Lease Expires . . . . . . . . . . : Thursday, January 24, 2019 3:17:17 AM
   Default Gateway . . . . . . . . . :
   DHCP Server . . . . . . . . . . . : 10.0.9.254
   DNS Servers . . . . . . . . . . . : 192.168.250.125
                                       192.168.0.11
   NetBIOS over Tcpip. . . . . . . . : Enabled

Tunnel adapter isatap.mydomain.com:

   Media State . . . . . . . . . . . : Media disconnected
   Connection-specific DNS Suffix  . : mydomain.com
   Description . . . . . . . . . . . : Microsoft ISATAP Adapter
   Physical Address. . . . . . . . . : 00-00-00-00-00-00-00-E0
   DHCP Enabled. . . . . . . . . . . : No
   Autoconfiguration Enabled . . . . : Yes

C:\Users\myuser>

nslookup:

C:\Users\myuser>nslookup ex-dc
DNS request timed out.
    timeout was 2 seconds.
Server:  UnKnown
Address:  192.168.250.125

DNS request timed out.
    timeout was 2 seconds.
DNS request timed out.
    timeout was 2 seconds.
*** Request to UnKnown timed-out

C:\Users\myuser>

I've tried to configure 192.168.0.11 (main DC) as the first DNS, 192.168.250.125 and 127.0.0.1 as the second and third. In that case:

C:\Users\myuser> nslookup
Default Server:  ex-dc.mydomain.com
Address:  192.168.0.11

> server 192.168.250.125
Default Server:  ex-dc2.mydomain.com
Address:  192.168.250.125

> ex-dc
Server:  ex-dc2.mydomain.com
Address:  192.168.250.125

DNS request timed out.
    timeout was 2 seconds.
DNS request timed out.
    timeout was 2 seconds.
*** Request to ex-dc2.mydomain.com timed-out
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