The Client over-writing the Physical adapter DNS servers is an expected behavior in a split tunnel configuration.
Settings that are discussed and noted in this article:
1. Split tunnel network configuration - Users > Resource policies > VPN tunneling > Split tunnel networks.
2. DNS server settings under Connection profiles. - Users > Resource policies > VPN tunneling > Connection profiles.
The following are the scenarios and behaviors seen with different PCS/ICS settings:
1. Only IPv4 resources configured under split tunnel networks:
>> Selected DNS settings under connection profiles and the corresponding behavior:
Search client DNS first, then the device - Physical adapter DNS servers are not over-written.
Search the device's DNS servers first, then client - Physical adapter DNS servers are not over-written.
Search Device DNS only - Physical adapter DNS servers are over-written.
2. Both Ipv4 and FQDN resources are configured under Split tunnel networks:
>> Selected DNS settings under connection profiles and the corresponding behavior:
Search client DNS first, then the device - Physical adapter DNS servers are over-written.
Search the device's DNS servers first, then client - Physical adapter DNS servers are over-written.
Search Device DNS only - Physical adapter DNS servers are over-written.
3. Only FQDN resources are configured under split tunnel networks:
>> Selected DNS settings under connection profiles and the corresponding behavior:
Search client DNS first, then the device - Physical adapter DNS servers are over-written.
Search the device's DNS servers first, then client - Physical adapter DNS servers are over-written.
Search Device DNS only - Physical adapter DNS servers are over-written.
