DNS configuration issue

[dreibh]

We are trying to connect some phones (LG Nexus 6P, HTC OnePlus) to our EPC. However, none of the phones get the DNS configuration from the SPGW-C settings. The phones simply seem to apply no DNS settings. The result is that the phones successfully connect to the mobile network, but do not have Internet access.
Our setup:
DEFAULT_DNS_IPV4_ADDRESS = "8.8.8.8"; # YOUR NETWORK CONFIG HERE
DEFAULT_DNS_SEC_IPV4_ADDRESS = "8.8.4.4"; # YOUR NETWORK CONFIG HERE
DEFAULT_DNS_IPV6_ADDRESS = "2001:4860:4860::8888"; # FFU
DEFAULT_DNS_SEC_IPV6_ADDRESS = "2001:4860:4860::8844"; # FFU
However, when configuring a VPN on the phones to bypass DNS queries to the mobile network, they work without problems. That is, connecting to the Internet via the EPC works fine when the mobile network is not used for DNS. Also, a Ping to 8.8.8.8 works fine as well. So, it seems that there is an issue with the EPC, which fails to provide the DNS settings to the UE.

Are there any known issues around DNS configuration? Are there some configuration options to check, in order to further debug this issue?

[dreibh]

The issue seems to be some incompatibility between EPC and UEs:
These devices have the DNS issue with our core:

• Nexus 6, Android 7.1.1
• Nexus 6P, Android 8.1
• OnePlus 6, Android 8.1.0
  However, these device are working as expected:
• Galaxy J7, Android 8.1.0
• Huawei E392 USB stick

[andresfocampo]

I have experienced the same issue.

In my testbed, I am using two OnePlus 6. For some reason, these model does not get DNS. Using a Samsung model, though, we get the predefined DNS, according to SPGWU conf file

[debashish216]

Are there any workaround for the phone models that can be applied? Please suggest. Thank you.