As a non-root user I would like to mount a samba share on my Fedora Linux with kerberos (non-password). I have a kerberos client running (sssd with the kcm server for kerberos tickets). when i do a klist, i can see that i have a valid kerberos ticket. So in theory i do not need to authenticate.
klist Default principal: myuser@AD.MY.BOX Valid starting Expires Service principal 11/09/2018 15:51:48 11/10/2018 01:51:48 krbtgt/AD.MY.BOX@AD.MY.BOX renew until 11/16/2018 15:51:48
but when i try to mount a samba share, which works if username and password is supplied, the kerberos mount fails. I believe, because it doesn't now how to get the ticket from kcm (https://docs.pagure.org/SSSD.sssd/design_pages/kcm.html) This is what i try to supply as mount
sudo mount -t cifs -o sec=krb5,user=myuser,cruid=myuser //my.box/public /mnt
It fails with
mount error(126): Required key not available
After looking into the manual i still have no clue how to tell mount to use the KCM server (assuming that my assumption is right, that the KCM server is supplying the ticket). What am I doing wrong? How can i mount without password?
Additional Information: The environment variable of KRB5CCNAME is set like this: