I've had OpenSSH server running on my debian server for a couple weeks and all of a sudden now when I go to login the next day it rejects my ssh key and I have to manually add a new one each time.
Not only that but I have the "tunneling with clear-text passwords" option enabled and the non-root (login with root is disabled) account for that is rejected too.
I'm at a loss why this is happening and I can't find any ssh options that would explain it.
I just changed debug level to DEBUG. But before that I'm seeing a lot of the following in auth.log
Feb 1 04:23:01 greenpages CRON: pam_unix(cron:session): session opened for user root by (uid=0) Feb 1 04:23:01 greenpages CRON: pam_unix(cron:session): session closed for user root ... Feb 1 04:36:26 greenpages sshd: reverse mapping checking getaddrinfo for nat-pool-xx-xx-xx-xx.myinternet.net [xx.xx.xx.xx] failed - POSSIBLE BREAK-IN ATTEMPT! ... Feb 1 04:37:31 greenpages sshd: Did not receive identification string from xx.xx.xx.xx ...
My sshd_conf file settings are:
# Package generated configuration file # See the sshd(8) manpage for details # What ports, IPs and protocols we listen for Port xxx # Use these options to restrict which interfaces/protocols sshd will bind to #ListenAddress :: #ListenAddress 0.0.0.0 Protocol 2 # HostKeys for protocol version 2 HostKey /etc/ssh/ssh_host_rsa_key HostKey /etc/ssh/ssh_host_dsa_key #Privilege Separation is turned on for security UsePrivilegeSeparation yes # Lifetime and size of ephemeral version 1 server key KeyRegenerationInterval 3600 ServerKeyBits 768 # Logging SyslogFacility AUTH LogLevel DEBUG # Authentication: LoginGraceTime 120 PermitRootLogin no StrictModes yes RSAAuthentication yes PubkeyAuthentication yes #AuthorizedKeysFile %h/.ssh/authorized_keys # Don't read the user's ~/.rhosts and ~/.shosts files IgnoreRhosts yes # For this to work you will also need host keys in /etc/ssh_known_hosts RhostsRSAAuthentication no # similar for protocol version 2 HostbasedAuthentication no # Uncomment if you don't trust ~/.ssh/known_hosts for RhostsRSAAuthentication #IgnoreUserKnownHosts yes # To enable empty passwords, change to yes (NOT RECOMMENDED) PermitEmptyPasswords no # Change to yes to enable challenge-response passwords (beware issues with # some PAM modules and threads) ChallengeResponseAuthentication no # Change to no to disable tunnelled clear text passwords PasswordAuthentication yes # Kerberos options #KerberosAuthentication no #KerberosGetAFSToken no #KerberosOrLocalPasswd yes #KerberosTicketCleanup yes # GSSAPI options #GSSAPIAuthentication no #GSSAPICleanupCredentials yes X11Forwarding no X11DisplayOffset 10 PrintMotd no PrintLastLog yes TCPKeepAlive yes #UseLogin no #MaxStartups 10:30:60 #Banner /etc/issue.net # Allow client to pass locale environment variables AcceptEnv LANG LC_* Subsystem sftp /usr/lib/openssh/sftp-server UsePAM no ClientAliveInterval 60 AllowUsers myuser