This solution applies to all Barracuda NG Firewalls utilizing the NG Network Access Client versions 2.0-SPx.
When connected over VPN with Barracuda NG Network Access Client, problems with the name resolution can occur if the internal and external DNS suffix are the same. This can be checked with the command ipconfig /all command at the client's operating system.
See this Microsoft Article for more information on DNS Namespace Planning. Most important is the point: ?..that the namespace that exists on the Internet not conflict with an organization's internal namespace..?.
VPN Resolution: Company users accessing the network from the Internet will be able to reach IP hosts in the public DNS zone, but will not easily be able to reach internal company resources inside the network perimeter without special (and manual) workarounds, such as maintaining hosts files on their machines (which must be manually updated as well everytime there is a change to an important IP host in the public zone), or they must use special VPN software (usually expensive).
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