I'm using OpenSSH 6.8 shipped with DSM 6 on my Synology NAS as a server, and OpenSSH 7.3p1 on my Arch Notebook as a client. I can login as the default user
admin via password, but not via key, and can't figure out why.
The strange thing is: the server seems to accept my public key, but still postpones it?
... debug1: userauth-request for user admin service ssh-connection method publickey [preauth] debug1: attempt 1 failures 0 [preauth] debug1: test whether pkalg/pkblob are acceptable [preauth] debug1: temporarily_use_uid: 1024/100 (e=0/0) debug1: trying public key file /var/services/homes/admin/.ssh/authorized_keys debug1: fd 5 clearing O_NONBLOCK debug1: matching key found: file /var/services/homes/admin/.ssh/authorized_keys, line 1 RSA SHA256:Kq+mYIESxPced3WZ0/GXkKeYxzn5aLI8P0S8MoVPll4 debug1: restore_uid: 0/0 Postponed publickey for admin from <client IP> port 43226 ssh2 [preauth] ...
I've already tried several restarts of both machines and the
sshd, and nearly all possible access permissions on user admin's home folder and it's
.ssh directory. But that doesn't seem to be the issue. What's faulty here?
Any ideas are greatly appreciated! Thanks in advance,
EDIT: The client says: "agent refused operation" after probing the key:
debug1: Offering RSA public key: /home/client/.ssh/id_rsa debug3: send_pubkey_test debug3: send packet: type 50 debug2: we sent a publickey packet, wait for reply debug3: receive packet: type 60 debug1: Server accepts key: pkalg ssh-rsa blen 279 debug2: input_userauth_pk_ok: fp SHA256:Kq+m*** debug3: sign_and_send_pubkey: RSA SHA256:Kq+m*** sign_and_send_pubkey: signing failed: agent refused operation
Furthermore, I've uploaded the complete output of both the verbose client and server sessions here.