dns resolution failed with IPsec VPN connected (IPsec XAUTH RSA) using iphone 5s

Hi,

I configured the Apple iOS Device ( Client-To-Site VPN) for IPsec VPN connection (IPsec XAUTH RSA). After configuring the Apple device, could able to connect to the IPsec VPN Server. After a few seconds, the VPN icon appears in the status bar to indicate that the connection is successful.

Using xCode package , collected the iPhone device logs . (Followed the procedure mentioned at https://support.kaspersky.com/12419). The below logs confirm that , IPsec VPN connection is established .

Device logs:

Phase 1/ISAKMP SA (IKEv1 Main mode ) establishment

Aug 26 15:19:45 iPhone racoon[562] <Notice>: IPSec Network Configuration established.

Aug 26 15:19:45 iPhone racoon(NetworkExtension)[562] <Notice>: >>>>> phase change status = Phase 1 established

Aug 26 15:19:45 iPhone racoon[562] <Notice>: >>>>> phase change status = Phase 1 established

Aug 26 15:19:45 iPhone nesessionmanager(NetworkExtension)[233] <Info>: IPSec Controller: PH1 ESTABLISHED. phase 3, assert 0

Phase 2 /IPsec SA (IKEv1 Quick mode ) establishment

Aug 26 15:19:46 iPhone racoon[562] <Notice>: IPSec Phase 2 established (Initiated by me).

Aug 26 15:19:46 iPhone racoon(NetworkExtension)[562] <Info>: IPsec-SA established: ESP/Tunnel 192.168.9.83[0]->72.22.171.100[0]

However with VPN established , unable to browse the google.com (using Safari ) and any other websites. Upon debugging found that , it does not send DNS query to DNS server. Please have a look into the below logs .

Oct 25 15:21:05 iPhone mDNSResponder[91] <Info>: ShouldSuppressUnicastQuery: Query suppressed for www.google.co.in., qtype AAAA, as the DNS server is NULL

Oct 25 15:21:05 iPhone mDNSResponder[91] <Info>: GetServerForQuestion: 000000010080A8C8 no DNS server (Scope None:0000000000000000:-1) found for name www.google.co.in. (Addr)

Oct 25 15:21:05 iPhone mDNSResponder[91] <Info>: InitDNSConfig: question 000000010080A8C8 www.google.co.in. (Addr) Timeout 30, DNS Server <<NULL>>:0

Can anyone please let me know where could be the issue ? please feel free to let me know if additional information is needed. Thank you in advance for your support and time.

Notes:

1. 1) I am able to browse different websites when VPN (IPsec) is not connected.
2. 2) However with VPN (IPsec) established, could able to ping to 8.8.8.8 Google Public DNS IP address) successfully (using ping tool on iPhone)

Regards,

Chinmaya