@panagiotis-milios Thank you for your response, appreciate your time !
I solved the issue :
The url I was using was wrong, more precisely I was using the wrong servlet :
I was using

/dispatcherv2

while I was supposed to use

/s2sdispatcher.

I also want to point out that you are right about the "appId" below the "packetId", it is not needed.
Thank you, I hope this thread will help anyone encountering this problem !

Hello,

I'm posting here because I'm out of idea on this issue.
I'm trying to establish a session based server to server connection, but I'm receiving a 40316 error code with the following message :

Processing exception (bundle): Missing app ID in nonauthenticated request

I'm using the following json as input :

{
	"packetId":0,
	"appId":"XXXX",
	"messages":
	[
		{
			"service":"authenticationV2",
			"operation":"AUTHENTICATE",
			"data":
			{
				"appId":"XXXX",
				"serverName":"####",
				"serverSecret":"SSSS"
			}
		}
	]
}

According to this link : https://getbraincloud.com/apidocs/portal-usage/using-postman-with-s2s/
it seems that the json is properly formed.
I also tried to rename the 'appId' to 'gameId' but in vain. (See https://getbraincloud.com/apidocs/apiref/#s2s-authentication)
Any idea what I'm doing wrong ?
Thank you for your time

Note : We run on R4.14.0-8281