I have a server equipped with Ubuntu 12.04.3 LTS. The OS is newly installed. But I can not connect to it with SSH from any other non-Ubuntu client include RHEL, putty.
When using SSH -v, the debug information is listed:
OpenSSH_4.3p2, OpenSSL 0.9.8e-fips-rhel5 01 Jul 2008
debug1: Reading configuration data /home/hk/.ssh/config
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: Applying options for *
debug1: Connecting to ..*.32 [..*.32] port 22.
debug1: Connection established.
debug1: identity file /home/hk/.ssh/identity type -1
debug1: identity file /home/hk/.ssh/id_rsa type 1
debug1: identity file /home/hk/.ssh/id_dsa type -1
debug1: loaded 3 keys
debug1: Remote protocol version 2.0, remote software version OpenSSH_5.9p1 Debian-5ubuntu1.1
debug1: match: OpenSSH_5.9p1 Debian-5ubuntu1.1 pat OpenSSH*
debug1: Enabling compatibility mode for protocol 2.0
debug1: Local version string SSH-2.0-OpenSSH_4.3
debug1: SSH2_MSG_KEXINIT sent
Then the connection hangs.
If connecting from a Ubuntu, it will be OK.
The sshd_config and ssh_config are completely the same to another Ubuntu 12.04.2 LTS server, which works very fine.
Where could the problem be ?