I have a CentOS system that I can connect to using several SSH clients (FireSSH, WinSCP, MySQL Workbench over SSH). For some reason, PuTTY, which was working a few days ago, can not connect. It will ask for a user name, then it sits until the server drops the connection. It never even asks for a password.
Any ideas on what could be wrong? There have been no changes to the server in that time, and since I can connect with other clients, I don't think it's a firewall issue.
=~=~=~=~=~=~=~=~=~=~=~= PuTTY log 2015.06.23 18:08:45 =~=~=~=~=~=~=~=~=~=~=~=
Event Log: Writing new session log (SSH packets mode) to file: putty.log
Event Log: Looking up host "x.x.x.x"
Event Log: Connecting to x.x.x.x port 22
Event Log: Server version: SSH-2.0-OpenSSH_4.3
Event Log: Using SSH protocol version 2
Event Log: We claim version: SSH-2.0-PuTTY_Release_0.63
Event Log: Doing Diffie-Hellman group exchange
Event Log: Doing Diffie-Hellman key exchange with hash SHA-1
Event Log: Host key fingerprint is:
Event Log: ssh-rsa 2048 xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx:xx
Event Log: Initialised AES-256 SDCTR client->server encryption
Event Log: Initialised HMAC-SHA1 client->server MAC algorithm
Event Log: Initialised AES-256 SDCTR server->client encryption
Event Log: Initialised HMAC-SHA1 server->client MAC algorithm
Event Log: Using SSPI from SECUR32.DLL
Event Log: Attempting GSSAPI authentication
Event Log: Server unexpectedly closed network connection