I am having troubles when I connect with my repository through Xcode.
I have a Gitlab version (full pre-)installed on TurnkeyLinux Virtual Appliance on a remote server.
I don't want to use HTTP! Key file under "git" user is very convenient and secure, I'm not going to type my password in a unencrypted URL entry in some plist file.
In my case, the problem was that Xcode was trying to use the wrong key file :
.ssh/id_rsa
.ssh/id_dsa