SSH Public Key Authentication only works if active session exists before
- by Webx10
I have a rather strange problem with my SSH configuration. I set up my server with the help of a Remote Access Card and configured everything with a KVM viewer.
So while being logged into the server via the KVM Viewer I configured SSH with only pubkey and tried to login from my local laptop. It worked fine.
If I quit the KVM Session (or logout with the user in the KVM session) I cannot login via ssh anymore (pubkey denied). SSH login only works as long as the user is somewhere still logged in.
Any hints what the problem might be?
Console output for a failed login (all personal data exchanged):
OpenSSH_6.2p2, OSSLShim 0.9.8r 8 Dec 2011
debug1: Reading configuration data /Users/mylocaluser/.ssh/config
debug1: Reading configuration data /etc/ssh_config
debug1: /etc/ssh_config line 20: Applying options for *
debug1: /etc/ssh_config line 103: Applying options for *
debug1: Connecting to 100.100.100.100 [100.100.100.100] port 12345.
debug1: Connection established.
debug1: identity file /Users/mylocaluser/.ssh/id_rsa type 1
debug1: identity file /Users/mylocaluser/.ssh/id_rsa-cert type -1
debug1: identity file /Users/mylocaluser/.ssh/id_dsa type -1
debug1: identity file /Users/mylocaluser/.ssh/id_dsa-cert type -1
debug1: Enabling compatibility mode for protocol 2.0
debug1: Local version string SSH-2.0-OpenSSH_6.2
debug1: Remote protocol version 2.0, remote software version OpenSSH_6.6.1p1 Ubuntu-2ubuntu2
debug1: match: OpenSSH_6.6.1p1 Ubuntu-2ubuntu2 pat OpenSSH*
debug1: SSH2_MSG_KEXINIT sent
debug1: SSH2_MSG_KEXINIT received
debug1: kex: server->client aes128-ctr [email protected] none
debug1: kex: client->server aes128-ctr [email protected] none
debug1: SSH2_MSG_KEX_DH_GEX_REQUEST(1024<1024<8192) sent
debug1: expecting SSH2_MSG_KEX_DH_GEX_GROUP
debug1: SSH2_MSG_KEX_DH_GEX_INIT sent
debug1: expecting SSH2_MSG_KEX_DH_GEX_REPLY
debug1: Server host key: RSA ab:12:23:34:45:56:67:78:89:90:12:23:34:45:56:67
debug1: Host '[100.100.100.100]:12345' is known and matches the RSA host key.
debug1: Found key in /Users/mylocaluser/.ssh/known_hosts:36
debug1: ssh_rsa_verify: signature correct
debug1: SSH2_MSG_NEWKEYS sent
debug1: expecting SSH2_MSG_NEWKEYS
debug1: SSH2_MSG_NEWKEYS received
debug1: Roaming not allowed by server
debug1: SSH2_MSG_SERVICE_REQUEST sent
debug1: SSH2_MSG_SERVICE_ACCEPT received
debug1: Authentications that can continue: publickey
debug1: Next authentication method: publickey
debug1: Offering RSA public key: /Users/mylocaluser/.ssh/id_rsa
debug1: Authentications that can continue: publickey
debug1: Offering RSA public key: /Users/mylocaluser/.ssh/id_rsa2
debug1: Authentications that can continue: publickey
debug1: Trying private key: /Users/mylocaluser/.ssh/id_dsa
debug1: No more authentication methods to try.
Permission denied (publickey).
Console output for a successfull login (only possible while "active session" exists):
OpenSSH_6.2p2, OSSLShim 0.9.8r 8 Dec 2011
debug1: Reading configuration data /Users/mylocaluser/.ssh/config
debug1: Reading configuration data /etc/ssh_config
debug1: /etc/ssh_config line 20: Applying options for *
debug1: /etc/ssh_config line 103: Applying options for *
debug1: Connecting to 100.100.100.100 [100.100.100.100] port 12345.
debug1: Connection established.
debug1: identity file /Users/mylocaluser/.ssh/id_rsa type 1
debug1: identity file /Users/mylocaluser/.ssh/id_rsa-cert type -1
debug1: identity file /Users/mylocaluser/.ssh/id_dsa type -1
debug1: identity file /Users/mylocaluser/.ssh/id_dsa-cert type -1
debug1: Enabling compatibility mode for protocol 2.0
debug1: Local version string SSH-2.0-OpenSSH_6.2
debug1: Remote protocol version 2.0, remote software version OpenSSH_6.6.1p1 Ubuntu-2ubuntu2
debug1: match: OpenSSH_6.6.1p1 Ubuntu-2ubuntu2 pat OpenSSH*
debug1: SSH2_MSG_KEXINIT sent
debug1: SSH2_MSG_KEXINIT received
debug1: kex: server->client aes128-ctr [email protected] none
debug1: kex: client->server aes128-ctr [email protected] none
debug1: SSH2_MSG_KEX_DH_GEX_REQUEST(1024<1024<8192) sent
debug1: expecting SSH2_MSG_KEX_DH_GEX_GROUP
debug1: SSH2_MSG_KEX_DH_GEX_INIT sent
debug1: expecting SSH2_MSG_KEX_DH_GEX_REPLY
debug1: Server host key: RSA ab:12:23:34:45:56:67:78:89:90:12:23:34:45:56:67
debug1: Host '[100.100.100.100]:12345' is known and matches the RSA host key.
debug1: Found key in /Users/mylocaluser/.ssh/known_hosts:36
debug1: ssh_rsa_verify: signature correct
debug1: SSH2_MSG_NEWKEYS sent
debug1: expecting SSH2_MSG_NEWKEYS
debug1: SSH2_MSG_NEWKEYS received
debug1: Roaming not allowed by server
debug1: SSH2_MSG_SERVICE_REQUEST sent
debug1: SSH2_MSG_SERVICE_ACCEPT received
debug1: Authentications that can continue: publickey
debug1: Next authentication method: publickey
debug1: Offering RSA public key: /Users/mylocaluser/.ssh/id_rsa
debug1: Server accepts key: pkalg ssh-rsa blen 279
debug1: Authentication succeeded (publickey).
Authenticated to 100.100.100.100 ([100.100.100.100]:12345).
debug1: channel 0: new [client-session]
debug1: Requesting [email protected]
debug1: Entering interactive session.
debug1: Sending environment.
debug1: Sending env LANG = de_DE.UTF-8
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