Warning: Split DNS is being used however no DNS domains are present
If a connection is using Split DNS, however no DNS domains have been set, Viscosity will add a "WARNING: Split DNS is being used however no DNS domains are present. The DNS server/s for this connection may not be used." warning to the log.
When Split DNS is used DNS requests for VPN specific domains for a connection will only ever use your VPN connection's DNS servers. For example, you can specify that DNS requests for "anything.example.com" should use your VPN's DNS servers by setting a DNS domain of "example.com". Likewise, DNS domains also act as search domains, allowing you to just type "anything" into your web browser to access the same server as well. DNS requests for all other domains will use your computer's normal DNS servers.
However if Split DNS is set for a connection, however no domains are associated with it, then the VPN DNS servers will essentially go unused. If the above warning is appearing in the log then this is the case. To resolve this issue and use Split DNS one or more DNS domains will need to be added to the connection in Viscosity, or pushed by the VPN server. For information on adding DNS domains to a connection please see Configuring DNS and WINS settings.
An alternative to using Split DNS is to use Full DNS. This will result in all DNS requests using your VPN DNS servers, not just those associated with the VPN connection. Please be aware that this may result in non-VPN network access to fail if the VPN DNS servers are not configured to handle all DNS requests.