How eNodeB gets the IP of the neighbour for initiating X2 Setup after CGI query in LTE

Hi Experts,

In Lte UE ANR after CGI query how serving enodeb knows about its neighbour ip address, so that it can initiate a X2setup to its neighbour, before adding it to NRT.

Source enb will send request to OSS to get ip address of target enb. OSS will forward request to target enb, send target ip address to source enb.

In which message it will ask for the ipaddress?

After CGI query ,The serving eNodeB would request to the MME the IP address of the eNodeB hosting the cell with that CGI and the MME after exchanging information with the target eNodeB would finally provide the IP address of the target eNodeB to the serving eNodeB after that, the X2 interface between both sites (serving and target) can be established and the neighbour relation tables in both eNodeBs are updated reflecting the new neighbour relationship.

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In which message the serving eNodeB would request MME for the ipaddress of the Target eNodeB?
In which message MME would request Target eNodeB for the ipaddress of the Ip address?

Below message for ANR concept

Serving Site:send S1: request X2 transport configuration to MME
MME:send S1: request X2 transport configuration to neighbor site
Neighbor site:send S1: response X2 transport configuration (IP address) to MME
MME:send S1: response X2 transport configuration (IP address) to Serving Site

Then X2 setup between seving & NBR site & NR table will updated

Sorry …I could not get the exact message …
Is it through ENB CONFIGURATION UPDATE and MME CONFIGURATION UPDATE messages?If not please specify the exact message… Thanks…

ANR Message

@cheikh789 …Thanks for the nice and clear description…Thanks a lot…

May I ask you…Which document you are following for this?

Nokia Vendor