SSH Key Certificates

I just tried it an di t doesn't work.

That's what I see on the server, when I try to identify with the 1P-IdentityAgent and the CertificateFile-option:

destinationhost# /usr/sbin/sshd -d -p 2222
debug1: sshd version OpenSSH_7.5, OpenSSL 1.0.2u-freebsd 20 Dec 2019
debug1: private host key #0: ssh-rsa SHA256:bQOMBvPw32zqCG9wAKku447CKX0VV0L8m3+Fcnidsws
debug1: private host key #1: ecdsa-sha2-nistp256 SHA256:5PzxSW/mxjC2KfZ/Sim0nAyzGD7GcEi4MFi4AbGi0r0
debug1: private host key #2: ssh-ed25519 SHA256:HDPsxjNsZuK7+53Re9n0foz4npqAW9CPJn+fa3xCNew
debug1: rexec_argv[0]='/usr/sbin/sshd'
debug1: rexec_argv[1]='-d'
debug1: rexec_argv[2]='-p'
debug1: rexec_argv[3]='2222'
debug1: Bind to port 2222 on ::.
debug1: Server TCP RWIN socket size: 4194304
Server listening on :: port 2222.
debug1: Bind to port 2222 on 0.0.0.0.
debug1: Server TCP RWIN socket size: 4194304
Server listening on 0.0.0.0 port 2222.
debug1: fd 5 clearing O_NONBLOCK
debug1: Server will not fork when running in debugging mode.
debug1: rexec start in 5 out 5 newsock 5 pipe -1 sock 8
debug1: inetd sockets after dupping: 3, 3
debug1: res_init()
Connection from xxx.xxx.xxx.xxx port 46136 on yyyy.yyyy.yyy.yyy port 2222
debug1: Client protocol version 2.0; client software version OpenSSH_8.6
debug1: match: OpenSSH_8.6 pat OpenSSH* compat 0x04000000
debug1: Local version string SSH-2.0-OpenSSH_7.5 FreeBSD-20170903
debug1: Enabling compatibility mode for protocol 2.0
debug1: permanently_set_uid: 22/22 [preauth]
debug1: list_hostkey_types: ssh-rsa,rsa-sha2-512,rsa-sha2-256,ecdsa-sha2-nistp256,ssh-ed25519 [preauth]
debug1: SSH2_MSG_KEXINIT sent [preauth]
debug1: SSH2_MSG_KEXINIT received [preauth]
debug1: kex: algorithm: curve25519-sha256@libssh.org [preauth]
debug1: kex: host key algorithm: ssh-ed25519 [preauth]
debug1: kex: client->server cipher: chacha20-poly1305@openssh.com MAC: <implicit> compression: none [preauth]
debug1: kex: server->client cipher: chacha20-poly1305@openssh.com MAC: <implicit> compression: none [preauth]
debug1: expecting SSH2_MSG_KEX_ECDH_INIT [preauth]
debug1: rekey after 134217728 blocks [preauth]
debug1: SSH2_MSG_NEWKEYS sent [preauth]
debug1: expecting SSH2_MSG_NEWKEYS [preauth]
debug1: SSH2_MSG_NEWKEYS received [preauth]
debug1: rekey after 134217728 blocks [preauth]
debug1: KEX done [preauth]
debug1: userauth-request for user user service ssh-connection method none [preauth]
debug1: attempt 0 failures 0 [preauth]
debug1: PAM: initializing for "user"
debug1: PAM: setting PAM_RHOST to "some.host.com"
user user login class [preauth]
debug1: userauth-request for user user service ssh-connection method publickey [preauth]
debug1: attempt 1 failures 0 [preauth]
user user login class [preauth]
debug1: userauth_pubkey: test whether pkalg/pkblob are acceptable for RSA SHA256:jzuBd+ulgpxou9emJu1RRvIn9bf6plMl0E4mhQLHZvU [preauth]
debug1: trying public key file /home/user/.ssh/authorized_keys
debug1: Could not open authorized keys '/home/user/.ssh/authorized_keys': No such file or directory
debug1: trying public key file /home/user/.ssh/authorized_keys2
debug1: Could not open authorized keys '/home/user/.ssh/authorized_keys2': No such file or directory
Failed publickey for user from xxx.xxx.xxx.xxx port 46136 ssh2: RSA SHA256:jzuBd+ulgpxou9emJu1RRvIn9bf6plMl0E4mhQLHZvU
debug1: audit_event: unhandled event 6
debug1: userauth-request for user user service ssh-connection method keyboard-interactive [preauth]
debug1: attempt 2 failures 1 [preauth]
user user login class [preauth]
debug1: keyboard-interactive devs [preauth]
debug1: auth2_challenge: user=user devs= [preauth]
debug1: kbdint_alloc: devices 'pam' [preauth]
debug1: auth2_challenge_start: trying authentication method 'pam' [preauth]
Postponed keyboard-interactive for user from xxx.xxx.xxx.xxx port 46136 ssh2 [preauth]
Connection closed by authenticating user user xxx.xxx.xxx.xxx port 46136 [preauth]
debug1: do_cleanup [preauth]
debug1: monitor_read_log: child log fd closed
debug1: do_cleanup
debug1: PAM: cleanup
debug1: Killing privsep child 825
debug1: audit_event: unhandled event 12