(SOLVED) Remote DNS not working over IPSec

pvn

I have a IPSec tunnel between two offices:

Office A:
domain: a.mydomain.com
LAN:    10.0.0.1/16

Office B:
domain: b.mydomain.com
LAN:    10.1.0.1/16

The machines in LAN A can ping and access the machines in LAN B and vice-versa by using IP address.

In office A in DNS Resolver Domain Overrides I have:

Domain:                   b.mydomain.com
Lookup Server IP Address: 10.1.0.1

In office B in DNS Resolver Domain Overrides I have:

Domain:                   a.mydomain.com
Lookup Server IP Address: 10.0.0.1

The problem: The pfsense DNS server that is remote to the client does not work at all. A machine in LAN A cannot resolve anything in LAN B and vice-versa.

From a machine in LAN A I can ping the DNS server in LAN B (10.1.0.1) and I can even telnet on port 53. But I cannot use it to resolve anything.
For example: (The following is executed from a machine in LAN A)

dig +short pfsense.b.mydomain.com @10.0.0.1 # this fails indicating that the Domain Overrides in the DNS Resolver does not work

dig +short pfsense.b.mydomain.com @10.1.0.1 # this fails indicating that the remote DNS cannot resolve anything

Trying to resolve internet domains using the remote DNS fails as well. The following is executed from a machine in LAN A:

$ dig +short netgate.com @10.0.0.1 # <- this is LAN A pfsense
208.123.73.73
$ dig +short netgate.com @10.1.0.1 # <- this is LAN B pfsense over the IPSec tunnel
$

Any ideas?

pvn

Problem solved.

LAN A subnet must be added to DNS Resolver ACL on pfSense B and LAN B must be added to DNS Resolver ACL on pfSense A
Services -> DNS Resolver -> Access Lists -> + Add
The "Action" should be "Allow"
The DNS Resolver "Outgoing Network Interfaces" in both pfSense must be set to "LAN" and "Localhost"
https://forum.netgate.com/topic/103395/dns-server-domain-override-over-ipsec-vpn-not-working