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Using DNS Client in PPP contexte

Hello,

I've have trouble using DNS Client service from MDK.

I use MDK-PRO 5.0.4 + STM32F4

The PPP is configured so that the "Obtain Client IP" and "Use Default Gateway" PPP option are both checked (but after investigating, nor of those option change anything).

The Primary and Secondary DNS server addresses parameter get the static IP of my two DNS servers.

The PPP is made over a 2G modem with a private APN.

When the link is established with the provider, I can see, using debug facilities, the assigned IP address but also an DNS IP server address (I think that this is the point to my troubles). This DNS IP server is not the one I have inputed in the PPP configuration.

006.6 PPP:*** Processing IPCP frame ***
006.6 PPP: Code  : Conf_Ack
006.6 PPP: Id_Val: 0x03
006.6 PPP: Length: 22
006.6 PPP: IP Address: 10.143.133.208
006.6 PPP:Network-Layer Up
006.6 PPP: Prim. DNS : 10.8.0.1   -> NOT THE GOOD ONE
006.6 PPP: Sec. DNS  : 0.0.0.0

So this result in a DNS Client query that always ends up in timeout status :

235.9 DNS:Resolve "xxx.yyy.jcdecaux.com"
235.9 DNS:Send request to Server
235.9 DNS: Serv.IP: 10.8.0.1      -> NOT THE GOOD ONE
235.9 DNS: Tran.Id: 0x1770
235.9 DNS: Flags  : 0x0100
235.9 DNS: QdCount: 1
235.9 DNS: AnCount: 0
235.9 DNS: NsCount: 0
235.9 DNS: ArCount: 0
235.9 PPP:Sending frame
235.9 PPP: Protoc: IP
235.9 PPP: Length: 77
236.9 DNS:Retransmitting request
236.9 DNS: Serv.IP: 10.8.0.1
236.9 DNS: Tran.Id: 0x1770
236.9 DNS: Flags  : 0x0100
236.9 DNS: QdCount: 1
236.9 DNS: AnCount: 0
236.9 DNS: NsCount: 0
236.9 DNS: ArCount: 0

and then ...

252.9 DNS:Retransmitting request
252.9 DNS: Serv.IP: 10.8.0.1
252.9 DNS: Tran.Id: 0x1770
252.9 DNS: Flags  : 0x0100
252.9 DNS: QdCount: 1
252.9 DNS: AnCount: 0
252.9 DNS: NsCount: 0
252.9 DNS: ArCount: 0
252.9 PPP:Sending frame
252.9 PPP: Protoc: IP
252.9 PPP: Length: 77
254.9 DNS-ERR:Resolve, Timeout expired

The same program using the ethernet interface in place of the PPP one is ok.

So, is there's a way to change dynamically the DNS server address so that it can be pointed to the correct one or there is no solution top this problem ?

Alain.