Ah, the authentication callback is used for hypervisor level authentication. You cannot provide credentials for SSH transport level authentication through the libvirt API. You'll need to setup the SSL certificates properly to enable automatic SSH login if you don't want to be prompted for the SSH credentials.
Matthias
Ohh... ok... it's not really what I want (because I could have many different machines to configure). Reading to libvirt sources (the c file) it seams that auth callbacks should be used also for the ssh code (inside openSSHSession method): virConnectCredential creds[] = { {VIR_CRED_PASSPHRASE, "password", "Password", NULL, NULL, 0}, }; if (!auth || !auth->cb) { PHYP_ERROR(conn, VIR_ERR_AUTH_FAILED, "%s", _("No authentication callback provided.")); goto disconnect; } maybe in some way it's possible to use ssh too with auth (I don't know but I want to try). Anyway, Matt, if I expose libvirt over tcp can I use it directly with provided callbacks? Thanks a lot Bye Marco -- Dott. Ing. Mornati Marco Byte-Code s.r.l via Antonio Cechov, 1 San Giuliano Milanese (MI) E-Mail: mmornati@byte-code.com